The Body Works thing is awesome. (Can you say 'slice and dice'?). Truly worth it. But heed the warning...get your TIME SLOT ticket in advance.

Also, if you are into nature, you may want to head to my part of Colorado, which is about an hour south of Denver (Colorado Springs) and check out Garden of the Gods. There is Seven Falls, you can check and see if the Cog Railway is operating. Depends on how much time you want to spend.