It's called MB3434 and you will find the whole project description including pictures & video @ http://letsmakerobots.com/node/40545
I've got inspired by this one, the nCee, also @ http://letsmakerobots.com/node/39856

All the parts are made with Google Sketchup. I just started drawing without any plan. All I had was the size of the motors and the L293. The battery and the Beetle basically set the size since they are the biggest parts. As I did it just for the parts I had lying around I am not sure how re-usable it is. But maybe you will get an idea how to modify it for your purpose.

The mold for the tracks is also 3D printed.
I used silicon mixed with some curing agent to make the tracks.

The robot is still work-in-progress and there might be some changes. It's running on a 550mAh Lipo, powering a DFRobot Beetle controller and using 2x QRD1114 as front and rear sensor.

NOTE: That's my first thingy and I hope you are able to use it. I am still trying to get everything right, e. g. rotating the parts of the mold. Make sure you check and double check before you start printing.