I just read them all (not in detail though, just browsing)
1995 - 97: Intel 80286 4MHz
1995 - 96: Intel 8086 4.5 MHz (IBM JX Personal Computer)
1997 - 2003: AMD 486SX 33MHz
1999 - present: Intel Pentium 2 350MHz (slot 1)
2001 - present: Intel Pentium 3 733MHz (socket 370) - now with my parents
2002 - present: AMD K6-2 533MHz
2002 - 2003: AMD K6 350MHz
2003 - present: Intel Pentium 3 733MHz (slot 1)
2003 - July '04: Intel Pentium 4-M 2.2GHz
August '04 - present: IBM PowerPC G4 1.07GHz (in iBook)
Edit: forgot this one:
2003 - present: Cyrix 486SL 25MHz