A starting point. 50,000 words is on the short side for a novel. Many novels can reach 75,000, 100,000, or even 200,000 words without breaking a sweat. Rather than attempting to start and finish a novel, why not just start one? There are no rules against not finishing your story by the end of the month... just hitting 50,000 words. So rather than trying to force yourself to write a contained story in that many words, why not start the process of writing a longer novel? By the end of November, you could have a quarter, or even half of a larger novel completed and be well on your way to finishing in December or January.

A template for something else. This is what I'm doing this year. Rather than working on something that I intend to be a novel in its finished form, I'm working on a story that I will eventually write as a television pilot. TV series can go on for years (hopefully!), and they require an immense amount of planning and preparation in order to play them out over the course of multiple seasons. Rather that writing a throwaway standalone product, I'm essentially going to attempt writing 50,000 words of backstory and narrative designed to outline where I want to go with the series. If you've got an idea for something besides a novel... a series of short stories, a TV show, a comic book run, etc., consider using NaNoWriMo as an exercise to help you figure out the overall story rather than trying to tackle it one installment at a time.

A jump start. This kind of ties into what I mentioned earlier about writing something designed to fuel my creativity. If you don't have any grand designs for a polished novel to submit to publishers, why not just write something that will get you back into a writing mindset? Whether you need to get back in the habit or are just feeling a bit uninspired, the commitment you have to make to undertake NaNoWriMo and the regularity with which you have to write are great ways to fire yourself up and get back to your writing habits. Even if you plan on keeping it saved in the deepest, darkest parts of your hard drive and never showing it to anyone, NaNoWriMo might be an exercise than can jump start something else for you.

A series of shorts. While there has been some debate about the use of vignettes in NaNoWriMo, the general consensus is that as long as the larger work has a unified set of characters, theme, etc., it's okay to have a work composed of smaller installments, like an epistolary or a series of shorts. Maybe a sustained 50,000-word narrative isn't your thing in the traditional sense of a novel... but maybe you've got a series of short stories you've been meaning to work on, or maybe you've got a particular theme you want to explore in a variety of different ways. If that describes you, NaNoWriMo might be the perfect way to explore different facets of a larger theme or character.