Advent calendars are originally German to celebrate and count down the days of Advent, climaxing in the celebration of Christmas Eve on December 24th.
Meanwhile, advent calendars are known in literally all cultures that celebrate Christmas.
The traditional calendar contains 24 randomly positioned doors on a cardboard. Starting on December 1st, one door per day, starting with door number 1, is opened. Behind the doors used to be little festive pictures. However, over the years pieces of chocolate have become more popular.
During the last third of the 20th century it has become a custom to handcraft more elaborate “calendars” that hold little gifts, such as chocolate, socks, nuts, pencils or anything else that is either delicious or useful. The calendar doors transformed into little sacks or gift boxes.
Today, online calendars are a modern way to share recipes, Christmas stories, traditions, poems or psalms. Some companies have set up advent calendars to give away gifts to their customers.
Here are 10 randomly sorted free online advent calendars from different backgrounds. They hold little surprises for you on each day of December up until Christmas.
1. Boowa & Kwala
An online advent calendar to countdown to Christmas with little seasonal surprises each day.

2. Presentation Magazine
There is no indication as to what this online advent calendar has in store, but my wild guess is that it is probably more suited for adults interested in improving their presentation skills.

3. Online Bingo
Do you enjoy Bingo? Then this one is for you! Since it’s a UK calendar, where Christmas isn’t celebrated until December 25th it has 25 doors. Each door will contain Bingo-related freebies and surprises.

4. Woodlands Junior School
This UK school has an interactive online advent calendar which shares 25 bits of information about how Christmas is celebrated around the world.

5. National Museums Liverpool
An educational and fun advent calendar.

6. Electric December
This website has been creating online advent calendars for over 10 years. Each year they collect films and digital treats to make up an incredibly creative and unique calendar. Watch out for what they have in store this year.

7. Yule in Iceland
This page educates its readers about Christmas or rather Yule celebrations in Iceland.

8. Greg’s Advent Calendar
Another 25 day advent calendar with little information treats behind each door.

9. St. Margaret Mary
This Christian advent calendar features a Bible verse and a matching image for each of 25 days until Christmas plus the two last days of November.

10. Holidays On The Net
Holidays on the net has compiled an advent calendar filled with facts, figures, and folklore related to the month of December.

About.com has a list of 25 advent activities with which parents and their children can countdown to Christmas. They also have many suggestions for handcrafted advent calendars.
If you speak German, check out this list for online Adventskalender or the following advent calendars: CHIP Online Download Adventskalender 2009, TATONKA Adventskalender, Toshiba & McAfee Adventszauber, MP3 Adventskalender 2009, Gedichte Garten Adventskalender, Weihnachten-Online Adventskalender 2009, Saarlouis-Roden Adventskalender, Weihnachtsideen24.de Adventskalender.
Did I miss your favorite free online advent calendar? Please hurry and share the link with the rest of us!
Image credits: mommyof9