The lab I work in at CMU is the inventor of the Gigapan system. I have used it plenty of times and it is always a great experience. I decided to build my own just for the fun of it.
It uses a dual-servo pan-tilt system to move the camera, and another one moves to push the button. It has a LCD screen to walk you through the steps of using it, and an IR remote is used interface with it. This allows you to stand back away from the system but still have complete control.
I custom built the pan-tilt system custom to the size of my camera. This allows it to be in a smaller overall package.
Here are some pictures of my system sitting next to the original one. A video of my system in action is at the bottom of the page.