When you say something different I assume you want to stay away from the Morton's/Ruth's Chris type high end steak houses? Here are a few thoughts...

Seafood (Yes, Denver actually has a couple of very good, fresh, seafood restaurants). McCormack's in LoDo is pretty good and they have an extensive menu of fresh seafood (flown in daily). Jax is right across the street is in an upscale raw bar type restaurant with a funky atmosphere. If you're looking for Northern Italian then there is Panzano. Its downtown in the Hotel Monaco. There's also Il Fornaio in LoDo. Yes, its part of a chain but you would never know it. Good Northern Italian food and a nice atmosphere. There are all sorts of good steak houses if that's what you are looking for (not all of them are chains). PM me if you have any other questions.