I use an IBM model M with a PS2-to-USB converter
:o)
I use a Unicomp Customizer. It's black/silver and has native USB. It
also uses the famous IBM/Lexmark buckling-spring mechanism.
BTW an old dream of mine is finding an IBM "M" keyboard with the
trackpoint (know as "clitoris" in Brazil...go figure! :oD). I'd love to
buy one, any info? :oD
sometimes has them. They appear to be
out of stock right now, though. You're looking for an "IBM Model M13".
Peace... Sridhar