Simply upload a suspicious file and click “Scan”. You will have wait several minutes before the scan starts and produces results for each antivirus engine.

Since it uses multiple online antivirus engines simultaneously, it is far more effective at detecting viruses and other threats than any single online antivirus on its own. That being said, VirusChief is not an only online virus scaner that uses virus definition from multiple engines, there is also VirusTotal, Filterbit and several more.

Features:

• Free online virus scanner.
• Scan suspicious individual files online for viruses and threats.
• Uses multiple online virus scan engines including AntiVir, Avast, AVG, BitDefender, Dr.Web and others (total 13 engines).
• View scan results for each antivirus engine.
• No registration needed.

Check out VirusChief @ www.viruschief.com

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• VirScan : Online Spyware Checker
• Panda Cloud: Free Lightweight Online Antivirus
• AVGLinkScanner: Real-Time Web Page Scanning For Threats
• QuickScan: Quick Online Antivirus from BitDefender
• Filterbit: Scan Files for Malware & Trojans Online

Features:

• Compress and unzip files within your browser.
• Zip as many files as you like.
• It runs in your browser, so there is no uploading of files to a server.
• Free and no sign up.

Check out ezyZip @ www.ezyzip.com

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• FileStomp: Zip Your Files Online
• Zip-Online : Online Zip Utility for Mac and Windows
• ArchView: Preview Zip Files Online
• Wobzip : Uncompress Files Online
• VirusChief: Free Virus Scanner Online

Just upload a file from your computer or from another URL, select input and output formats, enter your email and and click “Convert”. You will receive an email with the online download link for the converted file. Your file is kept for 7 days online after the conversion, so make sure you download it within this period.

Features:

• Easily convert anything to anything online.
• Supports almost all types formats including videos, audios, text documents, spreadsheets, images, archives.
• Upload a file from your computer or webpage.
• Receive the download link for the converted file in your email
• File is kept online for 7 days.
• Up to 100 MB file size limit.
• Similar converters: CometDocs, MediaPirate, YouConvertIt and Zamzar and several others.

Check out ConvertFiles @ www.convertfiles.com

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• Zamzar
• YouConvertIt : Online File and Unit Converter
• Top 3 Online File Converters (makeuseof.com)
• MediaPirate: Web Tool For Converting Files Online
• Media-Convert

Features:

• Get 50 GB of free storage.
• Maximum file upload size 5GB.
• No bandwidth limits.
• No sign up or registration.
• Password protect to your files (optional).
• Similar sites: Humyo, ADrive and Kadoo.

*Update : The maximum file size for uploading is now limited  to 200MB.

Check out FrostBytez @ http://frostbytez.com/files/Upload/

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• UploadGround: Upload Files to Several File Hosts at Once
• OrbitFiles: Keep and Share upto 6GB of Files Online for Free
• File123: Virtual Filing & Storage For Your Paper and Digital Files
• Zip-Online : Online Zip Utility for Mac and Windows
• Zapr: Share Files Over The Internet From Your Desktop

To compress, select a set of files on your computer and then click on the “Zip it!” button. Once the files are compressed you will get a link to download your .zip file. You can also then share that link with others.

Features:

• Compress files online.
• Zip as many files as you like.
• Download compressed file onto your computer or share it with others.
• Free and no registration.
• Similar tools: Zip-Online, OnlineZip and Wobzip.

Check out  FileStomp @ www.filestomp.com

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• ezyZip: Zipping and Unzipping Files In Your Browser
• Zip-Online : Online Zip Utility for Mac and Windows
• Wobzip : Uncompress Files Online
• OnlineZip : Online File Zipper
• ConvertFiles: Convert Almost Anything To Anything

The process of installation is usual, once installed a small icon appears on the status bar of your browser. When you click on .zip file link, ArchView will display the individual files and folders present in that .zip archive.

Features:

• Open zip files online.
• Open or download an individual file.
• Supports RAR and ZIP archives and ISO CD image.
• Supports HTTP, FTP and file protocols.
• Free and no registration.

Check out ArchView @ www.addons.mozilla.org/en-US/firefox/addon/5028 (via KillerTechTips)

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• FileStomp: Zip Your Files Online
• ezyZip: Zipping and Unzipping Files In Your Browser
• Zip-Online : Online Zip Utility for Mac and Windows
• WebSnapr: Free Website Thumbnail Screenshots
• VirusChief: Free Virus Scanner Online

Users may search for an extension using the search engine on top or browse file formats alphabetically. The site gives you info on the extension type (video, image, document, archive etc.) and description, list of programs that can open it and links to websites where you can convert the extension to another format.

Note: Every file on your computer has an extension at the end which indicates the type of information stored in that file. For instance, .doc file (thesis.doc) is a Microsoft Word document, .mp3 file is an audio file, etc.

Features:

• Easily identify unknown file types.
• Search for unknown extensions using search engine or browse by extension.
• Find out what the extension stands for and which programs can open it.
• Get links to the official extension webpage and places where you can convert it to another format.
• Similar websites: FILExt and OpenWith.

Check out FileSuffix @ www.filesuffix.com

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• OpenWith: Open Any File Extention
• Zip-Online : Online Zip Utility for Mac and Windows
• VirusChief: Free Virus Scanner Online
• OpenItOnline: Open Files Online
• Njouba: Search MP3s, Books, FTPs, Rapidshare & Torrents

You can convert 3 pages at a time without registration, signing up for an account will lift all the limitations and won’t require you to enter the email address every time.

Here is a list of online conversions CometDocs can do:

Convert from PDF: (some conversion support OCR conversion for scanned PDF)

PDF to Open Office Writer format
PDF to Open Office Calc format
PDF to Open Office Impress format
PDF to image BMP
PDF to image JPG
PDF to image GIF
PDF to image PNG
PDF to image TIF
PDF to text
PDF to HTML
PDF to MS Word
PDF to MS Excel
PDF to AutoCAD (dwg)
PDF to AutoCAD (dxf)

Convert to PDF:

Bmp to PDF
Word (doc) to PDF
Gif to PDF
htm to PDF
html to PDF
jpeg to PDF
jpg to PDF
log to PDF
mht to PDF
mhtml to PDF
ODF to PDF
ODP to PDFODS to PDF
ODT to PDF
PNG to PDF
PPS to PDF
PPT to PDF
RTF to PDF
SDA to PDF
SDC to PDF
SDD to PDF
SDS to PDF
SDW to PDF
SXC to PDF
SXD to PDF
SXI to PDF
SXM to PDF
SXW to PDF
TIF to PDF
TIFF to PDF
TXT to PDF
WRI to PDF
XLS to PDF

Convert from XPS:

Convert to Open Office Writer format
Convert to Open Office Calc format
Convert to Open Office Impress format
Convert to image BMP
Convert to image JPG
Convert to image GIF
Convert to image PNG
Convert to image TIF
Convert to text
Convert to HTML
Convert to MS Word
Convert to MS Exsel

Other File Conversions:

Excel to CSV (XLSTOCSV)
XML to LINT (XMLLINT)
HTML to RSS (HTMLTORSS)
ASC TO PDB
ASC TO EBC
UNIX TO DOS
DOS TO UNIX
MAC TO UNIX
FIX TO DELIM
DELIM TO FIX
CSV TO DELIM
SORT FILE
PDF INFO
COMPARE FILES
MP3 INFO
FILEINFO
ICONV

Features:

• Comprehensive file and data converter app.
• Performs over 50 different file conversions, see list above.
• Non registered users can convert only 3 pages at a time.
• Registering on the site lifts all the limitations.
• Free and simple to use.
• Similar web tools: MediaPirate, YouConvertIt, Zamzar and several others.

Check out CometDocs @  www.cometdocs.com

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• MediaPirate: Web Tool For Converting Files Online
• PDFtoWord: Accurate PDF To Word Converter
• ConvertPdfToWord: PDF to Word Doc Converter
• Acrobat : 5 in 1 Online Office Suite from Adobe
• WebMarkers : Print Documents To Web

Programs are grouped according to file types like images, audio files, spreadsheets, videos and so on. Just search for the right program using the file extension name. Next, download the program on to your computer and open the file.

Features:

• Helps to open almost any file extension for free.
• Lists lots of freeware programs to open any file files.
• Search for particular program or browse alphabetically.
• Download the program or get it from software developers’ website.
• Free, no registration.
• You may also check out OpenItOnline, a browser tool that can open certian documents, images and other file types without the need to download and install a software for it.

Check out OpenWith @ www.openwith.org

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• Wakoopa – Discover Cool Software
• Softonic : Popular Software Directory
• SnapFiles
• FileSuffix: Identify Unknown File Formats
• AppWorldBlackBerry: Directory of Paid & Free Applications for the BlackBerry

Here is the list of supported formats:

- Text Documents (*.doc, *.rtf, *.odt, *.sxw)
- Presentations (*.ppt, *.pps, *.odp, *.sxi)
- Spreadsheets (*.xls, *.csv, *.ods, *.sxc)
- Images (*.jpg, *.gif, *.png)

The add-on works with Firefox: 1.5 – 3.1b3pre. Once you have the add-on installed every time you get the “Open With” dialog within Firefox it will also display ”Open IT Online” option among the others. You only need to select which online service you would like to open it with

Moreover, you can set it as default for different file types.

Features:

• Opens documents, spreadsheets, images and presentations online.
• Eliminates the need of particular software.
• Shows the file size before opening it.
• Customizable defaults for each file type.
• Works with Firefox: 1.5 – 3.1b3pre.
• Unable to open attachments of emails and  PDF files.
• Free and no registration.

Check out @ Open IT Online (via appscrazy.com)

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• Unlinker: Quickly See Full Images Behind Links or Thumbnails
• SiteLauncher: Launch Favorite Websites with Simple Shortcuts
• SearchBastard: Firefox Advanced Search Add-on
• MXPLAY: Music Player for the Web
• MultiLinks: Multiple Link Opener & Bookmarker

The process is straightforward simply go to the site, select both files and click on “Compare Files” button. The application will compare files side by side and show you lines where they are different.

Features:

• Comparing two text files online.
• Compare as many files as you want.
• No registration needed.
• Dead simple to use

CompareMyFiles @ www.comparemyfiles.com

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• DirectTextbook: College Textbook Price Comparison Site
• Wowbrary: Get Alerts on New Book Arrivals From Your Library
• WordCountTool: Tool For Counting Words in Text
• WiZiQ : Virtual Classroom
• wePapers: Student Paper Database to Find & Share Notes

- search the web and find free mp3s online
- search for videos on video sharing sites
- search images
- search for files on FTPs
- search web for PDF e-books
- search Rapidshare content
- search torrents

All of these search tools can be accessed in different tabs on a single page.

It shows the links to the files on the respective sites. This could be a very useful search site for sure.

In the following screenshot, I searched the rapidshare tab for the query ‘Dark Knight’ and it immediately showed the related downloadable files in Rapidshare.

Certainly a handy search tool. It is also available in different languages. Give it a shot.

Check out Njouba @ www.njouba.com ( Contributed by Abhijeet from Jeet Blog )

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• ShareMiner: Search Web for Files
• Usniff: Search Multiple Torrent Sites Simultaneously
• TorrentSurf: Search 14 Leading Torrent Engines At Once
• TorrentMetasearch: Search Many Torrent Sites At Once
• TorrentFly: Search 13 Torrent Sites at Once

Additionally, if you’re a developer and would like to install similar PHP script on your own website and offer your readers the same functionality then you can download the script from here. It’s easy to install and manage.

There is also a service called Wobzip. It does the opposite of Zip-Online and allows people to upload and unzip archived files online. Quite useful if you need to uncompress the archive file that is not supported by your main archive manager (i.e. Winzip or Winrar). Wobzip works with 7z, .ZIP, .GZIP, .TAR, .BZIP2, .RAR, .CAB, .ARJ, .Z, .CPIO, .RPM, .DEB, .LZH, .SPLIT, .CHM, and .ISO formats.

Check out Zip-Online @ www.zip-online.net

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• FileStomp: Zip Your Files Online
• ezyZip: Zipping and Unzipping Files In Your Browser
• Wobzip : Uncompress Files Online
• VirusChief: Free Virus Scanner Online
• ShrinkFile: Free Online File Zipper