Motor shield

Is there a decent motor shield available for driving cheap little hobby motors? I'm familiar with the Ladyada and Freeduino products, but their current capability is much too low. The cheap little Tamiya motors take up to 2.2 amps and at a lower voltage than these shields can put out.

I know the problem here is they're cheap quality motors, but that's the kind of thing I'm trying to use here, and cheap little toy cars have the same type of motors, so I can't be the only one with this problem.

You can make your own. There are H bridge IC's available that can handle more current than the ones in the commercially available shields. It's not very complicated if you are only going to control one or two motors.

You can even make your own H bridge circuit out of discrete components like heavy duty Darlington transistors with heat sinks and diodes. I think i have a link to such a design at home. I'm at work right now, i will look for the link and post it here when i come home. The downside of this is that it will probably be more expencive and take up more space than a heavy duty H bridge IC.

There is a less elegant but functional way to use the current shields with more power. The L293b could handle 1 amp per channel, so if you want more power you simply could iron another L293b above the one mounted on the shield(now you have 2 amps). It's a bit crappy but works.

It's amusing to picture a stack of 10 chips soldered pin to pin in a vertical column out from the PCB. As far as I know though, these chips won't work with the cheap low voltage motors (can they go as low as 2-3 volts?).

I was looking forward to playing with Ladyada's library for her own shield, so if I built my own circuit from discrete parts, it would have to be compatible.

On the other hand, is there a reasonably cheap alternative to the Tamaya dual gear box that will work with higher voltage lower current motors? Though that's not ideal either because I can't use their mechanical parts or hack a toy car.