Digital Research had one also, the CP/M Gold Card.  192K of memory, 4Mhz
Z80, etc.
    --jc
Fred Cisin wrote:
 On Sat, 8 Oct 2005, Brent Hilpert wrote:
 show me up as the ignorant one: nobody ever
bothered to rewrite CP/M (which to
my understanding was all targeted to Intel procs) for the Apple II did they?
 
Microsoft "SoftCard".
Z80 co-processor card for Apple ][, bundled with CP/M.
At one point, there was a claim that 20% of Apple ]['s had one!