I've found another one that I like, not so much for any specific effect it produces within play, but for it's versatility.
3:16 is a pretty simple game on the surface, it uses a basic mechanism where you roll a 10 sided die and aim to roll under your designated skill level. The higher your skill level, the better your chance to roll under it.
But the instant advantage that a system like this provides is that it allows a method of comparing two opponents without resorting to additions, subtractions or other modifiers. As long as both participants succeed in their roll, simply compare the numbers. Higher value wins.
It's elegant because it combines two effects into a single die roll.
I'd like to find a good use for this in a game, but at the moment I've got too many other ideas circulting in my mind.