The KayPro 2x was a portable CP/M system, not hugely portable weighing in at around 13kg, but very small for its day. It had a built in 9" green monitor, and a 5.25" disk drive, whilst the keyboard attached to the case for travelling. The KayPro 2x's main claim to fame is that Arthur C. Clarke wrote 2010 on one.
This driver seems to be quite fast but unfortunately wouldn't go past the startup screen.
Speed Rating:
StrongARM 
Technical details
CPU - Z80 running at 2.5 MHz.
Display - 80x24 character display, no graphics capability or character
attributes (flashing, inverted etc.)
Sound - Simple VDU driven beeper, the keys click when pressed
which can be turned off in software.
ROM - 2kb
RAM - 64kb
reference -
Machine Room