Facebook Graph Search is an amazing feature with a terrible name. It takes the massive, inordinate amount of personal information and experiences you've charted over the years, and pulls them up with a few keystrokes. Watch it in action.
Although Graph Search isn't as speedy as I'd like -- not as smooth as Google -- the thing is still a beta. It's also a massively intensive process, scouring piles of data you didn't even know existed. But speediness aside, it's a lot of fun. Put aside utility for a moment. Open Graph gives you a new way to reflect on yourself online, and for a billion vain internet denizens, a new way to self-obsess (or hey, even self-examine) is tremendous. Timeline made your Facebook life beautiful. Now Open Graph is starting to feed it directly into your brainpan. This is a nostalgia crack pipe.
And, sure, it's useful -- I can't imagine many people clicking around the Facebook cosmos when they can just search through it instead.