Gizmag has a great overview on haptic technology, from the infancy of the N64 rumble pack to the latest cutting edge technologies...ahem that's us.

Haptic technology: The next frontier in video games, wearables, virtual reality, and mobile electronics

Competitive gaming is a fierce business, and in a world where online multiplayer is cutthroat, it can be difficult for the gamer to get an edge up on their opponents. That’s where KOR-FX comes in. With our innovative technology, you can feel your enemy’s vehicles approaching, or detect the direction of incoming sniper rounds. It’s the kind of advantage that can take your competitive gameplay to the next level.

KOR-FX is completely tweakable, and you can fine-tune your experience based on your personal preference or the type of game you’re playing. You can adjust the depth of field of the environmental feedback, change the amount of differentiation between the left and right audio channels, or amp up the intensity to the bone-rattling levels. With the forthcoming Dev-Kit, developers or enthusiasts will be able to games with KOR-FX in mind. Try it with titles like Counter-Strike: Source, Call of Duty, or Arma 3 and you’ll never want to go back to the old way of playing again.