What game mechanics from other systems have you pulled into your Pathfinder game?
Bennies from Savage Worlds
I'm using Hero Points (but not Hero Point-based feats, spells, or magic items), and I've decided that I want to use them like Bennies from Savage Worlds. I actually give my players counters that represent their Hero Points, and the counters are of two sorts. Glass beads represent regular Hero Points that can be stockpiled (up to three max). One is given out at every Character Level, and I award additional ones for awesomeness during the game. I also hand out one "Session Point" (represented as a gold coin). This additional hero point resets at the end of each session.
Minions from Dungeons and Dragons 4th Edition
I don't use them all the time, but I do occasionally use minions, as per D&D 4e. These work great for letting the heroes fight through hordes of bad guys, all of which have a possibility of actually hurting the PCs, but go down in one blow. Very cinematic. My players love this!
Abstract Combat from AD&D
Sometimes, I throw the battlemat out the window (figuratively), and run a combat abstractly, like in old-school AD&D (and retro-clones like OSRIC or Swords & Wizardry). No tactical positioning, no five-foot steps, no carefully calculating the positioning of where the fireball lands. I usually do this for less-than-crucial fights, or for free-wheeling melees like a large barroom brawl. My old-time players love the break from what they see as the combat mini-game. I have to ad-hoc rules that rely on tactical combat (e.g. the Step Up feat), but my players don't object. It can really speed up throwaway or impromptu combats.
Advantage and Disadvantage from D&D 5e
I am intrigued by the concept of Advantage and Disadvantage from D&D 5e: When a character has Advantage, he makes two d20 rolls and takes the better; when a character as Disadvantage, same thing but has to take the worse roll. I'm not quite sure how to implement this yet, but I'm thinking!