Note: follow the advice below at your own risk!
Ever noticed how you can't get a recent (Catalyst) Windows driver for the ATI graphics chips in some Thinkpads? I'm thinking of the ATI Mobility Radeon 9000 in a T40, the 7500 in an R40… there are probably others. If you try to install a recent Catalyst driver, there's a warning about the INF file not being found.
It turns out that the current drivers can be installed, but only after some gentle persuasion. This page explains how, and provides a tool to let you install them. You'll need the .NET framework to get it to work.