Regardless of price, I
really want Hasu's thing. It's just about perfect: mounting holes (mainly), PS/2 socket etc etc.
Saw this in one of those links, any reason it would not work?? Would I have to do anything to it to get it to function like a teensy??
http://www.hobbytronics.co.uk/atmega32u4-arduino-breakout
Be careful with that breakout board. It's literally just the chip sodlered onto the board. There's no crystal, or voltage regulators or anything. I'm not sure, but I think you'll need more to get it working than just a USB cable and pull resistors.
looking at the below, I think you'll end up spending more in associated hardware to get it working:
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