If you are asking about strictly new phones, the exibit 2 is probably your best bet.
If you're willing to go used, then you have a lot of options. Check ebay, craigslist, and local pawn shops. I picked up a galaxy vibrant for 100 from a pawn shop. I've seen htc sensations for 200...among others. I choose the cheaper route as I'm planning on buying a G nexus when I have the money.