Ah yes, KeyRemap4Macbook seems to work. I saw that earlier, but thought it was Intel-only. There's an older release that works with PPC.
I enabled "Keypad as Arrow" and that works nicely. [strike]I tried remapping left Command to "`", but that doesn't work at all.[/strike] I wish I could remap the power button to Sys Req, but I don't see that anywhere.
Edit: For Command remapping, you have to Remap backquote to Command... instead of the other way around.