Every year since 2006, I've done NaNoWriMo, which runs in November. This year, however, I discovered that there is also a summer version: Camp NaNoWriMo.
Camp NaNoWriMo runs both this month, June and in August (at least that's how it is this year). The camp version is a little less structured than the original November challenge, which involves a lively forum, write-ins, and other events such as kick-off and TGIO (thank god it's over) parties. Instead, Camp NaNoWriMo puts you into a "cabin" with as many as five other participants, and you have a message board that allows you to communicate, cheer one another on, and so on. The goal -- 50,000 words -- is the same as the November version, however.
If you love fiction and have always wanted to write, or if you just need a kick in the pants to keep you writing, NaNoWriMo is perfect for you. Having a daily goal will help you make some substantial progress in your novel this summer, even if you don't actually finish. I love using NaNoWriMo as motivation to get me going on my writing, so I was especially excited to see it now runs during the summer -- and two separate months, too!
We are already more than halfway through June, of course, so unless you think you can write really fast, you may not want to try it this month -- but August is still an option, and you even have a month and a half to prepare!