Wed May 23, 2012 12:54 pm
...This might be contrary to your actual question, but have you thought about replacing the X61? I picked up an X61s last year (the ultra-low voltage variant) for only £170, which included a docking station and shipping. You wouldn't have to worry about how much RAM it has or the hard drive size as you should just be able to drop in the hardware from your existing machine.
My little X61s has been an utter trooper; it was already 4 years old when I got it, but the battery still has 85-90% of original capacity (according to the Lenovo monitoring applications) and lasts a good 4-6 hours. It doesn't have the best screen in the world, but it does the job damn well. After switching to Lubuntu almost full time it's even nippier; even though it only has a 1.6GHz processor (albeit a Core2Duo). I am well and truly sold on ThinkPads after getting mine!