In preparation for the FTC competition, I've been getting familiar with RobotC, the language we're planning to use. In order to test my programs, I built a small rover that uses treads. Since the new plastic treads don't have good traction, I used the black rubber treads. Now, I don't think I've ever gotten a really good design with these treads! They're so small that it's hard to really secure them to the outside of a robot well. When I'd make a rover with these treads sticking out on both sides, I had trouble with the treads bending out and the chassis "sagging". So this time, I tried spreading the weight out more evenly, by positioning the motors directly above the treads. The result was really nice... a very strong and compact design that had no trouble with wheel camber. I even found a snug little place for the Ultrasonic sensor. :-) 
Notice that the treads are connected to the robot from both sides, increasing the strength of the chassis. This is possible since the treads are underneath the robot.
I souped up the gear ratio a little, which gave the rover some pretty decent speed while not diminishing the power too much.
Here's a video of the rover in action...
-Jonathan