My current rig is "Elysium". My laptop is "Rurouni". My old PC, soon to be sold, was "Avalon". Workgroup's called Excalibur.
My gf's PC is "Athena". My old 286 and 486 were called "Cause" and "Effect". My old printers, a LaserJet II ("Whirlwind"), and a dot matrix ("Banshee"). When I lived at university, my housemates had some fun names: "Waitress" (for the server), "Icebox" (because the guy's frat name was Fridge), "Sinbox" (he had Sextris shared), "Bob" and "Billy" (the redneck), and "H.a.L. 9000", although I had to get that changed because the dots in "H.A.L." was messing up access to that guy's network share.