I just moved from NYC to New Haven, CT, so have kind of seen both ends of the spectrum here. Having just done rent that was half of my take home pay, I'll say that it's not enjoyable, especially because everything else is more expensive as well... food, transit, parking, you name it. In New Haven, my rent dropped by about $800, but everything is a 20 minute drive away from the small walkable downtown. Some thoughts...
What is your commute situation? Are you at home during the day, or is this a job-in-the-opposite-direction problem? Think about the possibility of a one-car household with a slightly longer commute, does it make any sense? Then you can get some of the benefits of both situations. I never would have considered going without a car before I lived in Manhattan, but now a combination of trains, walking, and biking gets me most everywhere I need to go on a daily basis, and we still have one car for longer trips (Zipcar also helps). If one if you can get your regular commute to public transit, a single car won't be enough to offset the rent benefits.
Long commutes are the worst, but on the other hand, so is automatically using up 80%+ of your take home on rent/food/transit. It's just tough to feel like you're making any progress.