Rocket Copter
I've seen versions of these that didn't really work. This thing, well... it goes! You are going to need to print several blades if you live anywhere near trees because that's where all of mine ended up, in the tree branches. This thing easily gets 30+ feet without any special tricks or genius level printing. You don't need to be a rocket scientist is what I'm saying :) Hint: A little Vaseline on the handle will help it launch with little effort. You may need a raft for the prop depending on your printer, the good news is that no supports are required.