ORIGINAL: patmat
The smallest fully proportional & reversing ESC I've found is the Airtronics ES-01, about $25 at Tower, handles small motors just fine. And many people just use a hacked servo for drive, the electronics provide reversing and a bit of proportional control.
Pat M
HOLY COW!
I will see about buying one for myself then, I need like 6 of those units for projects of the Submarine flavor :-)
Mark