I am totally a fan of Wicked Chili on 17th. From the outside, the look like a run-o-the-mill low-budget Indian food place, but inside waits a great buffet of standard Indian food greats, really attentive servers and the freshest Naan bread you've ever had.
The buffet is $13, which is pretty decent, and though the selection may not be that of, say, Rajdoot, which is a bit further down 4th street and a few dollars more- what this place offers is superb, and the service alone deserves two thumbs up.
I've been to this place a handful of times ( I live and work near by) and would recommend it to anyone. Try it out - support these new business owners and have some really tasty Indian Food while you're at it!