They're not all insane. Personally, I'm partial to the slow but effective gravity tow: send a small, 1-ton spacecraft and have it sit right next to the asteroid

They're not all insane. Personally, I'm partial to the slow but effective gravity tow: send a small, 1-ton spacecraft and have it sit right next to the asteroid, without impact. If you place it correctly you can alter the orbit however you like. Of course, the danger is that this could be used for evil, too. But it's not that crazy, and it would most definitely work.