Document this work in anyway necessary to prove to the world that you've made something new: write, take pictures, videos, post things online.
Do this everyday and post to the blog before midnight, 7 days a week.
You can upload pictures straight to this blog (limit to 200K per post) but you can also host your work anywhere online and post a link to it on the blog. If you have a Flickr account, use it please.
Introduce your daily accomplishments: give them a name, a title, a punch line, a description, anything that will encourage others to check out your work.
See what everyone else has been up to and steal ideas, comment on other people's work or reinvent something they did.
No recycled old work, no posting someone else's stuff unless you have explicit authorization from them. We'll welcome anyone who wants to join and we trust you know the basic net ethics (-we reserve the right to kick someone out if/when needed).
Thing-a-day.com will not send you reminders, will not harass you or threaten you if you don't do your daily post, once you sign up, you're on your own.
Yes, registration closed on January 31st at midnight and it started February 1st so you can't really play this year - unless you create on your own for the rest of the month. However, you can remember Thing-a-day for February, 2009.