R/C robotics and battlebots.
The components that I used are hard to find now, but the good thing about this instructable is that it applies to all sorts of speed controllers, motors, and R/C equipment.
Step 1: Materials
1 R/C transmitter (Mine is a 5 channel, Spektrum DX5e)
1 R/C receiver (Mine is a Spektrum AR6115e, it has to be compatible with the transmitter)
1 Speed Controller***** (Mine is a Sabertooth RC-12 Dual)
2 GEARED Motors (I have no idea what mine are, I bought them from a friend)
2 Wheels for motors
1 X-Acto knife
1-2 Batteries (mine are 7.2v 1600mAh)
1 piece of foam board as big as your robot
10-20 Zip Ties
Wire (mine is stranded 18 awg copper wire)
***** The Speed Controller is what will kill you (figuratively) if you do not pick the right type. You want a dual channel 5-10 amp speed controller which will power your receiver.
Step 2: Setup
After you have that complete, you will want to mount the wheels onto your motor. This may be easy or hard depending on the motors, but mine were fairly easy because the hubs were already attached and glued. There is a very small little screw on the side which will tighten it against the flat part of the shaft. Just do that to both motors and you are done! Also, if your motors do not have soldered wires you will want to do that.