NaNoWriMo is National Novel Writing Month and it works. You can write a novel in a month. I am. It may not be readable by anyone but you. Mine isn't. But to write your 50,000 words in 30 days, you will need to be swift and not judge your writing. This is the surest way to overcome writer's block.
From the NaNoWriMo.org reason #3: Art for art’s sake does wonderful things to you. It makes you laugh. It makes you cry. It makes you want to take naps and go places wearing funny pants. Doing something just for the hell of it is a wonderful antidote to all the chores and “must-dos” of daily life. Writing a novel in a month is both exhilarating and fun, and we would all do well to invite a little more spontaneous whimsy into our lives.