I bought my son one of these electric model R/C copters for his 9th birthday, and I'm embarrassed to say I've played with it more than he has. It is an indoor flyer, remarkably stable, and while the flying time is 5 minutes with a charging time is >30, it is amazingly good otherwise. I am NOT affiliated with Amazon or the company who makes these, but considering the venue, I thought I'd pass along the good news.
It's almost scary to think that someone in China can sell these at $20 retail and make a profit. The frame is actually metal (thin steel perhaps, judging from the finish), and the whole thing is rather durable, all things considered. It's a highly recommended aeronautical chachkie.
I have a couple of these, and I agree that they're great fun. There's a really big thread on RCgroups dedicated to them.
It's a little bit hit-or-miss. One of mine flies great, but the other suffers from "toilet bowl effect."
I've seen these but, where/how do you get parts? Something even as simple as blades.
Amazon sells parts too. I've crashed mine into walls and light fixtures countless times with no ill effects. For $20 bucks, if you're really worried about parts, buy two of them. ;-)