Arduino is a wonderful platform to rely on to learn electronics and experiment on robots. The RobotGeek Geekbot is an Arduino compatible rover with a modular design. It has a payload capacity of 1kg and moves at fast as 0.4 mps. The rover is powered by 2 high speed servos and runs on a 2200 mAh battery.
Thanks to the robot’s Geekduino microcontroller, you can always expand its capabilities. Simply buy and add sensor arrays, turrets, grippers, arms, lasers, and controllers. As you can see in the above video, you can use Geekbot to deliver drinks. Costs $139.95 at this time.