The next time you find yourself in Vegas for whatever reason, do yourself a favor and take an hour or two to visit the Pinball Hall of Fame. It's not glamorous, it's kind of dark, and it's just about the opposite of everything that you typically experience on the strip. What it does have however are pinball machines and classic video arcade machines - tons of them - and all of them are playable.
They have proto-pinball machines from the fifties, classic pinball machines from the seventies (Ted Nugent or Elton John pinball anyone?) as well as the newest pinball machines on the market. They've also got machines sized specifically for kids, all the classic video arcade games you'd expect, and even an extremely rare stand-up pinball machine prototype, of which only three were made. The "Hall of Fame" aspect is pretty thin - there are handwritten cards with information on each machine, but really it's all about playing.
And unlike just about everything else in Vegas, it's a non-profit so all of your hard-earned quarters are going to keep the place going, and then the rest goes to charity. Plus, there's a great dark English pub a few doors down (the Crown & Anchor) and a place to fire machine guns up the street (The Gun Store). It will pretty much make the perfect afternoon while the wife/girlfriend is at the spa.
The Pinball Hall of Fame in Vegas in Las Vegas is a short cab ride from the strip. Check it out at PinballMuseum.org.