Because it would be too easy to simply put my new 1 GB memory module in the user-accessible location on the bottom of my Thinkpad (one captive screw, incredibly easy to remove), I attempted to remove the keyboard in order to get at the memory module that is located beneath the keyboard. In the process, I manage to "strip"[1] three of the four screws that keep my keyboard in my laptop. However, the real ultimate power of having 1.5 GB of memory made this worth it.[2]

From page 68 IBM's Thinkpad Computer Hardware Maintenance Manual from my computer (T43 2668W12):

Never use a screw that you removed. Use a new one. Make sure that all of the screws are tightened firmly.

While I am glad that IBM/Lenovo will use completely new screws if my laptop ever goes in for service, I am not sure how serious to take this, especially as IBM's "screw kit" (the only way to get new screws, since the ones that IBM provides are special nylon-coated screws) costs $36.

I did experience strange problems, but I was able to fix them by reseating the memory modules, not by using new screws.
[1] strip - to destroy the "drive" of a screw so that it cannot easily be removed.

[2] A large part of the reason I bought more memory is the fact that Evolution, the Linux PIM program that I use, has horrible memory leaks. After a number of times of leaving Evolution running for a couple of hours and realizing that my computer had ran out of free memory, because Evolution was using 300 MB or so, I had enough. While that no longer occurs, other programs do seem to be using more memory. Like goldfish growing to fill their bowls/tanks/the New York City sewers, Linux programs seem to adapt to the amount of memory available.

I would use Thunderbird (like I normally do when I use Linux), but I really like having a calendar and tasklist. I like to pretend that it helps me get things done.