I used to fly, drive and sail anything that has a motor and was under the control of a radio. I gave it up years ago because of the expense at the time, but would really love to get back into it one day.
In the interim, I came across this R/C flight simulator on the advice from Mark Suchting (Satchmo), who is also into radio control and currently flies full-sized gliders for a hobby:
http://www.realflight.com/free-g3-demo.html
It's an 80Mb download, but one you run it you'll see two demo aircraft - a .40-powered high-wing mono plane and a .30-powered helicopter. The physics is sophisticated and after flying the real thing these things feel just the same on screen. It's quite uncanny! Brill fun!