I just bought a thinkpad T61p and love it! Been searching to buy a thinkpad for a long time but since my old laptop now died I immediatly ordered one! Ok it has a bit extra weight but it's not like i drag it around everywhere.
You should have a look at thinkwiki, there you find nice manuals for installs of a lot of operating systemsn and tweaks, settings and packages to support the specific hardware, I can recommend it to every hacker out there!