Keyboard with hardware text buffer?


I've been looking for a keyboard that has a hardware buffer (for text) that
can be used to copy/paste text across different platforms while using a KVM
switch. The different platforms are running different OS's, so what I'm
really after is something that is done completetly at the hardware level
(i.e., no drivers to handle the copy/paste).

Even better, if it works closely with a mouse. (Keyboard stores text, spits
it out, from mouse gestures.)

Anyone ever come across such an animal?