Thanks to RasPi.Today for this one.

Thanks to a simple I2C expansion board, you can now add touch and gesture recognition to your Raspberry Pi. The board, called simply the ‘Hover’ is $39 and plugs into the I2C pins on the Pi (as well as power and ground). It can recognise up, down, left and right sweeps and also touches on the board itself. They’ve written a how-to guide for the Pi on their website and it looks pretty straight forward. Not sure on shipping costs, but expect it to be $10-15 extra (this is just a guess, feel free to correct me!). Take a look at their website for more details or see it in action on the Pi below.