I bought a cheap keyboard from PC World because I found I didn't have any usb keyboards in the house. (Although I could find 3 DIN connected keyboards and a pile of PS/2)
Anyway the keyboard wouldn't work. connecting it to the pi immediately crashed the o/s.
A new firmware fix committed to git somewhere around 25th July seems to have solved this. I used rpi-update to update the firmware. It's fairly painless, and the keyboard seems to be working now.
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