Hotel spas, like most amenities in Las Vegas, are designed to wow and envelop guests in sheer bliss -- which only makes the competition that much stiffer. After visiting all the spas and weighing them against each other, we considered not only their size and reputation, but also the breadth and originality of treatments, the comfort and design of the facilities, and the level of service from the staff. Whether you need to cleanse and rejuvenate your body after a night of hardcore Vegas fun or unwind after a trade show, these spas are our top picks for pampering.