Dude, i would explain but i am off for dinner....i odn't meant o be nasty but please search for these terms...
mobile athlon (obviously)
and you will find some posts that have talk of mobile athlons
Also look up the recent(ish) thread titled "Intel or AMD" or summit like that.
MatrixPc and a few others run mobile athlons. The onlt board so far known to be able to run one without any dodgy mods is the biostar as if has full fsb and mutiplier control. The AOpen one in a thread i started today might - gonna do some more digging around for info on it.