For some gyms, towel service is just the beginning.

Across the nation (and world, in one case), fitness facilities are upping their game to attract the most exclusive clients, including professional athletes, Wall Street gurus and celebrities. And while a membership will cost you a pretty penny (at Bosse Sports and Health Club in Subury, Mass., for instance, monthly membership is $389 after the whopping $4,000 initiation fee), you'll have plenty of cool new toys to encourage you to hit the gym.

Here's a look at some of the world's most luxurious gym amenities: