RC Arduino Robot
Looks like not to much to put one together. Maybe I'll give it a try!
Tamiya 70157 Universal Plate Set (2pcs.)
Tamiya 70100 Track and Wheel Set
Tamiya 70168 double gearbox
He's got his own motor controller; here's a ready-built serial model:
Pololu low-voltage dual serial motor controller
Low-Voltage Dual Serial Motor Controller + Tamiya Double Gearbox Combo
This motor is recommended as an upgrade over the stock motor:
Brushed DC Motor: 130-Size, 6V, 11.5kRPM, 800mA Stall