We can't say we are surprised someone has developed this little gadget. In fact we are surprised it hasn't been done sooner than now. Simon Ford, who happens to be the Director of Tools from ARM, has created a USD slingshot to use when playing Angry Birds to get that a little closer to feeling yourself truly flinging a bird and stone block and wood planks.
Taking the slingshot, adding an accelerometer to it which measures to the tilt/angle the slingshot is at, then adding the rubber strap which will do the dirty work on flinging said bird and having it embedded with a sense to measure how far back he pulls, Simon has officially made Angry Birds a lot more interactive with his creation. You can check this little gadget out in action in the video below.
All the measurements that the accelerometer and the rubber sensors take are matched up with corresponding mouse controls to actually give this slingshot fairly precise aiming. Last, but not least, the slingshot is outfitted with a USB connector and a mbed NXP LPC11U24 Microcontroller so you can actually use this device. Not too shabby although we are not sure if this could be used with an Android device. It is probably possible though.
If you want to take a shot at building your own, all the instructions are available in the mbed cookbook.