More information here.
I love GYWO. It's a yearly challenge community dedicated to hitting a certain word count over the course of twelve months. I dig it because it's a type of low-pressure NaNo; the highest possible word count is 350K, and you have 365 days over which to spread your rough patches rather than 30. I've been playing since the comm was founded, and it's a great tool to keep you on track and working steadily if NaNoWriMo falls at an inconvenient time for you. The mods are also super-sweet and keep the comm well-stocked with inspirational exercises and writing prompts. Definitely looking forward to my fourth year bopping along!
NOTE: You do need a Livejournal in order to participate in this challenge, but signing up is free, and the mods don't particularly care if it's an active journal or not just so long as it's there. Makes it easier for them to keep track of participants.