Any trip to Vegas for me always includes a stop or two at Rhumbar. I usually like to start my night out on the town with a drink from Rhumbar (not that I haven't been drinking all day by that point!). I love the laid back atmosphere. The outdoor patio is a fantastic spot to just kick back, relax with friends, smoke a cigar or hookah, and enjoy a rum-based cocktail. I'm quite the rum fan and they have a pretty extensive rum selection. Generally just order it on the rocks with a splash of coke. The Zaya is one of my fav's.
They usually have a DJ after 10, and they are generally pretty good. Not a place I come to jam out to music though. If you are walking by the Mirage, definitely make a pit stop in for a drink and a little break from the chaos known as Vegas!