I'm sure most of you have heard of write or die at some point, which I guess you could consider the stick method -- keep writing or I'll make annoying sound/start deleting your words.
Written? Kitten! On the other hand, uses much more of a carrot method, for every 100 words you right, you're given a new photo pf a very pretty kitty! There's also a puppy counterpart, for those of you that are dog fans :D
