A while ago I started considering doing those 30-days challenges. The benefits are obvious, and the fact they're published gives motivation to actually stick to the plan.
So, I already have several such challenges in mind, and some were already started. For example, taking the stairs instead of the elevator in the building I'm living in. I'm on the 4th floor, so it is a "free exercise".
Another thing I had in mind for a while now, is using twitter. It happens to me every day: There's some new technology I want to blog about, but when I start thinking about the actual post, I realize it would take me no more than 2 lines. For example: I installed Firefox 5, and thinks it's great.
So instead, I opened a twitter account (@technomosh), and I'm planning to post those short musings there. Hopefully people will follow me, and discussions would develop.
What does this have to do with 30 days challenge? Simple. Basically, up until now, I wasn't a big believer in Twitter/Identi.ca/Buzz/etc. So my first instinct is to ditch the Twitter account a second after I opened it. Instead, I just installed the wonderful TwimGo on my N900, so it would be easier for me to post some tweets. Hopefully, in 30 days I'll know whether Twitter helped me in getting those musings off my head, or didn't.