[Question] Unique game mechanics -- The best and the worst

I've been thinking a lot about this game since Qwarky mentioned emulating it in his journal a little while back. Been trying to come up with a good av/sig set for it.

Umihara Kawase's fishing line (under the "best" category)

The game concept, attaching to surfaces with a hook and swinging around a level, is not unique. The grappling hook was a big part of getting around in Bionic Commando, for instance. But no game has gone about the concept the way that Umihara Kawase did.

Instead of having a rigid line attached to the hook, the main character throws an elastic fishing line around. So, you can hook the bottom of a ledge and swing up around the corner to the top; hook onto the floor, walk backwards, and slingshot yourself forward quickly; rappel down and scale up vertical walls; and do all sorts of other cool stuff with the physics engine, which is one of the best ever written. It works fluidly and perfectly; I've never encountered any choppiness or glitches while swinging around levels.

The game is very short, but that doesn't matter at all because it's so much fun just playing with that goddamn fishing line.

Jam it back in, in the dark.