Want to make a Mac OS X user’s head explode? Exit their running copy of Quicksilver and ask them to restart it. “Why that’s easy… you just use Quicksilver to… OH DEAR GOD!”
I’m not even really joking. Quicksilver is that embedded. It’s like a direct pathway from your brain to your computer. I panic a little bit whenever I’m on another computer and I tap the Quicksilver activation combo without thinking… it’s like being unable to use your hands.