23 Days Until NaNoWriMo

In 2009, over 160,000 people from all over the world participated.  I was one of them.  Over 30,000 crossed the 50k finish line.  I was one of them.  When it was over, I swore I wouldn't do it again.  So, why did I sign up for 2010?  For me, it's an addiction, that's why.  It's almost a challenge. 
When I signed up, I envisioned a room full of people, their arms crossed in front of their chests, smirks plastered on their faces saying, "Yeah, sure.  You'll never do it."  
It's a valid excuse to sit in front of my computer screen and type until it hurts, just so I could say, "Wanna bet?" 
There are no prizes, no money, just a really large sense of accomplishment and with any luck, a rough draft for a novel.  Probably with a whole bunch of nonsense mixed in, but a rough draft nonetheless.  And that, my friends, is a huge step towards publication. 
Granted, I haven't even looked at my manuscript from last year, but that's alright.  One of these days, that rough draft just may get dusted off and worked on.  Until then, I need to start outlining this year's novel. 
Have you ever heard of NaNoWriMo?  Have you done it?  Would you ever attempt it?