My mentor in all things remote-control, Mark Harrison has written a pretty cool Instructable on how his flying buddy Andreas built a simple but reasonable quadcopter in only an hour.
Here is the cool timelapse, ending with a short flight after fifty-one minutes elapsed:
Mark has more details and photos here, as well as some realtime construction video. Andreas originally did it as a friendly wager, but I think there is lots of good material here, not the least of which is just the inspiration of seeing someone build a quadcopter in a reasonably short amount of time, using equipment that isn't very esoteric. Yes, you need the motors, props, ESC and flight control board, but other than that, it's basically wood and screws.
Thanks to Mark and Andreas for posting this.
Addendum: Moments after posting this, I noticed this new video by David @ flitetest on constructing a tricopter from scratch:
If you are at all interested in RC stuff, flitetest is highly recommended: lots of cool information, lots of good forums, and even some cool kits.