You've got to try Karve -- it's the best workout -- EVER! It's basically a combination of ballet barre work, core conditioning and stretching. It's a one hour class that is challenging and a lot of fun. I've been taking the class for about nine months and I feel stronger and leaner.
The instructors are great too. I can't say I have a favorite -- they're all a ton of fun and inspirational.
Oh, and word on the street is that they're opening a Karve Studio in Scottsdale...can't wait for that!