USB X-keys by P.I. Engineering

Quick Comparison of USB and PS/2 X-keys

	USB	PS/2
OS	Best for Windows 2000/XP/Vista & Macintosh OS-X.	Works on any OS which accepts PS/2 keyboard.
Installation	Requires Macro Works or iKey software (included)	No software or driver required. Just plug it in.
Commands	Accepts all keyboard commands and sequences, mouse, multimedia, launches applications, opens files and folders, and supports custom scripting.	Accepts all keyboard commands and sequences (mouse clicks supported via Windows Accessibility options).
Programming	Programs in software. Very versatile, easy to edit and save multiple layouts.	Programs in firmware. Incredibly simple to program and operate.
Portability	Layout is stored as a data file, easily copied to multiple computers.	Programming is saved in on-board, non-volatile memory (no external file required).
Memory	Each layout file can save more than 100,000 keystrokes for the entire unit.	On-board memory holds 900 to 1,000 keystrokes for the entire unit.
Distance Limitation	Up to three meters with standard cable. Up to 150' (45.7 M) with X-keys USB Extender	Up to 50' with standard cable. Up to 100' with Y-key key Adapter