DRZ400SM!!!! Solid motors, cheap on gas, and when you (or your buddy) wrecks, its is super cheap and easy to fix. I love mine, although it hasnt been getting much ride time since I got my 09 ZX6R....
I agree with the others about the SV. I have one as well, and know many many other people that love theirs. A very good overall bike, especially for the price.