My main motivation in building this was to use it to telepresence with my family back in the north east. I figured this would be a lot more fun and interesting than just the usual Skype session.
The design is pretty simple: a motorized base with a laptop up top and a webcam. The base has two geared brushed motors which are controlled by the laptop via USB. I used a Maestro from https://www.pololu.com/ which lets you control standard r/c equipment from a PC. I then wrote a little C# windows app which connects to the Maestro and then could control the motors. This app also could connect to another instance of itself over the internet in either a master or slave mode which would allow external control.
The webcam was mounted on a simple gimbal which allowed pan/tilt control for general looking around. All the video and audio communications were done through Skype.
The coolest part of this project was getting to play with the robot controls and creating new operating modes, different controls methods for user interaction and etc. Piloting a robot from 3000 miles away was also pretty cool, although internet latency really sucks.
I almost put a pair of nerf guns on this to add a little more fun to the mix. If I ever do another telepresence robot I'll have to add some offensive capability to it.