I think mine were 240X, X41t, X60s, X61s and now X301, while my wife had T42, T62 and now X220. Not all were excellent - the T42 and X60s in particular had letters wear off the keyboard caps, but most were great, especially the X61s and X301. The X220 is nice and pretty solid, but I still prefer the X301's bigger screen, SSD and lighter weight. The only things I miss are there's no SD-card reader or docking station.
An updated X301 with say an i7 chip, 16 or 32GB, SD-reader, docking port, at least 2500 by something screen, and a higher capacity battery would be great. Sadly it would probably cost at least a grand, whereas I can pick up and fully pimp out a second-hand original X301 for £200, tops.