Main rig (the one in sig): xp x64 (before i used xp mce 2005) 2nd rig: xpsp2 office: w2k3sp1 Also, proud owner of: 3.1, 3.11, 95, 98se, 2000 (pro and server), xp professional (x32, x64), xp mce 2005, w2k3, vista (although enthusiast at the beginning, now don't like it too much, maybe until the final version will come out).