I participated in NaNoWriMo this year. Don't know what that is? It stands for National Novel Writing Month, and it's in November. Participants challenge themselves to write 50,000 words in one month.
Crazy, right? But totally fun. I didn't "win" this year (read: reach 50k), but I had a ton of fun sprinting for it. It was great to have a community writing event. Typically, writing is such a solitary thing, but with this, there were others encouraging you, and you knew they were striving for the same goal. Groups of writers did write-ins together, too, gathering in one place with their laptops or paper and pens and madly scribbling/typing words together.
If you're interested, the site for it is nanowrimo.org. It doesn't start again until November 2010, but there's plenty to do in the forums until then!