Freezly allows you to search for current giveaways using keywords, check which free deals are hot and browse archive of past giveaways.

Features:

• Tool for finding free stuff that people giveaway on Twitter.
• Aggregates tweets only with free stuff and ranks them based on retweets.
• Check out the hottest free deals and browse past giveaways.
• Free, no registration needed.
• Also see How To Get Companies To Send You Free Stuff With No Catches.

Check out Freezly @ www.freezly.com

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• MakeUseOf 'Geeky Fun' - Hillarious Geeky Pics and Videos from different parts of web.

• You Serials : Adware-free Serial and CD Key Search Engine
• Yammer – A Twitter For Businesses and Enterprises
• wwwitter: See Twitter Discussions For Any Webpage
• Wowio : Download Copyrighted eBooks for Free. Legally.
• WitGuides: Find And Download Ebooks

Features:

• Free science ebooks (textbooks, lecture notes) in different subjects.
• Read ebooks online or download them in PDF format.
• All listed texts are offered legally on the site and have been authorized by their respective authors and publishers.
• Similar sites: Project Gutenberg, Wowio and eBooksDB. Also check out earlier MakeUseOf article on The Best 6 Sites to Get Free Ebooks.

Check out ScienceBooksOnline @ www.sciencebooksonline.info

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• MakeUseOf 'Geeky Fun' - Hillarious Geeky Pics and Videos from different parts of web.

• WitGuides: Find And Download Ebooks
• Wowio : Download Copyrighted eBooks for Free. Legally.
• PDFse: Search for PDF Files on Google
• PDFind: PDF Document Search Engine
• PDFgeni: Comprehensive eBook Search Tool

For those of you who are not really interested in creating an eCard, you can browse through hundreds of user made eCards, and find your favorite. Someecards cover a wide range of topics, from babies to birthdays to movies. You’re sure to find something you’d like. Users can also vote on their favorite cards, as well as send premade cards to their friends and family. There are a ton of uses for Someecards. Whether it is out of love or hate, Someecards is the place to go to send others your favorite eCards.

Features:

• Make your own eCard for free
• Create your own eCard with a picture and your own text.
• Vote on your favorite eCards.
• For those using Facebook, you can use the Someecards’ Facebook App.
• Find e-cards for just about every occasion.
• Share your favorite eCards with your friend or family.

Visist Someecards @ www.someecards.com

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• You Serials : Adware-free Serial and CD Key Search Engine
• You Don’t Know Jack
• YearbookYourself: Give your Photos 1950s, 60s, 70s …. look
• XSketch : Online Multiplayer Pictionary Game
• Write Like An Egyptian

Raffstar is a relatively new website that’s in Beta Testing, but anyone is welcome to create an account and getting tickets to win prizes. The concept of the website is extremely simple. Items will be put up for raffle, and depending on the type of giveaway it is, you will be able to get a certain number of tickets a day. In a speed giveaway, you can get a new ticket each hour. In the standard giveaway, you can get a ticket every day. When the raffle for the item is over, a ticket is chosen at random and the winner will receive the price. Naturally, if you get more tickets, you have a better chance at winning.

There are also different types of raffles. Some raffles are over when a certain number of days pass, no matter how many tickets have been taken. Others are based on the number of tickets taken. When a certain number (say 20,000) of tickets have been taken, the auction is over. This is a great place to try out your luck and win a few prizes. It’s also good to know that you’re supporting charities at the same time and you can always donate your price if you want to.

Features:

• Raffle and win prizes for free.
• No limit to number of tickets one can take. Only a limit on how often.
• Take tickets for multiple items at once
• View list of previous winners and what they won.
• Browse through a dozen of different items up for raffle.

Check out RaffStar @ www.raffstar.com

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• MakeUseOf 'Geeky Fun' - Hillarious Geeky Pics and Videos from different parts of web.

• You Serials : Adware-free Serial and CD Key Search Engine
• Wowio : Download Copyrighted eBooks for Free. Legally.
• WitGuides: Find And Download Ebooks
• TravelGuidesFree: Free Travel Guides & Brochures
• Someecards: eCard Making & Sharing Online

There are two ways to search for brochures and travel information. You can either click on the map and find a region that interests you or click on one of the 30 plus states shown on the  sidebar.

Features:

• Get free travel guides and brochures.
• Receive them by postal mail or download on to your computer.
• US and Canada only.
• No signup needed.

Check out TravelGuidesFree @ www.travelguidesfree.com

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• ZimRide: Carpooling Website To Find & Share Rides
• You Serials : Adware-free Serial and CD Key Search Engine
• Yapta: Get Refund on Flight Tickets
• Wowio : Download Copyrighted eBooks for Free. Legally.
• WorldTaximeter : Taxi Fare Calculator

Moreover, you can also check out the recent additions (under ‘New Ebooks’) and most popular books (the most downloaded ones), rate and leave comments.

For more ebook resources I highly recommend you to go through our excellent round up article “The Best 6 Sites to Get Free Ebooks“.

Check out WitGuides @ www.witguides.com

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• MakeUseOf 'Geeky Fun' - Hillarious Geeky Pics and Videos from different parts of web.

• Wowio : Download Copyrighted eBooks for Free. Legally.
• ScienceBooksOnline: Free Science eBooks
• PDFse: Search for PDF Files on Google
• PDFgeni: Comprehensive eBook Search Tool
• eBookHood: Convert Text, Webpages, RSS Feeds to iPod Format

AppDonkey has one really useful feature, while browsing the site you can keep adding programs you like to the virtual tray and then download all of them at once in a single .tar file.

Features

• Directory of free mac applications.
• Search and browse apps by category.
• Currently lists over 500 handpicked free apps for Mac OS X.
• Download multiple programs at once.
• No signup or registration needed.

Check out AppDonkey @ www.appdonkey.com

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• FreshAirApps : Directory of Adobe AIR Applications
• Ziipa: Web 2.0 Directory
• YuuGuu : Free Desktop Sharing Software
• You Serials : Adware-free Serial and CD Key Search Engine
• Wowio : Download Copyrighted eBooks for Free. Legally.

There are plenty of popular websites that offer free serials and CD Keys. The problem with most of such websites, they are full of adware and spy bots. In exchange for a serial number or CD key people are asked to sign-up or install some kind of craplet. A quick Google search for ‘some commercial program serial’ should give you a pretty good idea about how hard it is to find a working serial.

You Serials is probably the cleanest serial and CD key search engine out there. As stated on their website, “the website is designed to provide its users with a directory of information of serial numbers which is compiled by other users…”.

It claims to have neary 55.000 serials (Microsoft Office, Windows XP, Windows XP Pro, Nero 8 Ultra Edition, Adobe Photoshop, Microsoft Office 2007, Plus Microsoft Office 2008, NOD32 Antivirus, etc). There is no need to sign-up or install anything. Search, Find and Copy the serial. It also shows the most popular, top 100 and recently added serials and CD keys.

Furthermore, there is a browser addon that lets you search on YouSerials without going to the website first.

Check out You Serials @ www.youserials.com

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• Zillow
• YouTorrent : Torrent Comparison Search Engine
• Yahoo Glue: All Search Results On One Page
• Wowio : Download Copyrighted eBooks for Free. Legally.
• WoonzFiles: Search Rapidshare, MegaUpload, Megashares …

Features:

• Downlod free eBooks to read on your computer or mobile device (PDA, iPhone, iPod, cell phone etc.).
• Search for ebooks or Browse by category, latest additions, popular, recent downloads, etc.
• Most of the ebooks can be downloaded in several different fomats.
• Over 20.000 eBooks available and more added every day.
• Some ebooks also available in audio format (see screenshot).
• Tips on how to convert PDF ebook to make it compatibe with your mobile device.
• It’s 100 free. No sign up or email required.

Go to ManyBooks @ [ www.manybooks.net ]

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• Wowio : Download Copyrighted eBooks for Free. Legally.
• WitGuides: Find And Download Ebooks
• TextOnPhone : Over 30.000 eBooks for Your iPhone
• SmokinApps: Discover Latest Mobile Applications
• ScienceBooksOnline: Free Science eBooks

How does it work?

• 1. Find the book/s you want and add it to download queue.
• 2. When you are ready to get your books, go to the ‘Queue’ section.
• 3. Click on the “Gee Ebooks” and download button will appear next to each book.

Features

• Search, find and download copyrighted ebooks.
• Browse books by popularity or genre (architecture, art, classics, computers, college textbooks, fiction etc.)
• Limitation: You are allowed to download at most three books/day and not to exceed 30/month.
• Due to licensing restrictions service available only in United States.

[Video] Wowio demo

Check out Wowio @ www.wowio.com

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• MakeUseOf 'Geeky Fun' - Hillarious Geeky Pics and Videos from different parts of web.

• WitGuides: Find And Download Ebooks
• ScienceBooksOnline: Free Science eBooks
• Project Gutenberg : The Ultimate Source of Free eBooks
• PDFse: Search for PDF Files on Google
• PDFgeni: Comprehensive eBook Search Tool