I actually did the NaNoWriMo thing several years ago. I found it grueling because I ran out of inspiration after about the first week but still had to put in a daily output of words to get to the 50,000 word goal. If you complete the word total, they send you a certificate that you can print out. I felt a little like Jack Nicholson in "The Shining" toward the end. If you remember, wife Shelly Duvall finds out that Jack has been writing, "All work and no play makes jack a dull boy" for hundreds of pages.