aprilfoolsnovels.com is sorta like NaNoWriMo in April -- except you set your own word count goal (500 minimum) and can change it whenever you want. I've forgotten about it for a few years in a row, but when I got the reminder email today I thought, "Hey! Great opportunity to get some writing done!"

http://aprilfoolsnovels.com/forum/index.php

It's all on a forum, and even more of an honor system than NaNoWriMo is.

Have fun!