In my last post I mentioned that I am playing games on a 1.5Ghz Celeron with an Intel 915GM/GMS,910GML Express Chipset. The system is actually a Gateway laptop with 2GB of RAM, Windows XP Home Edition and a 60GB hard drive. It's not optimal for gaming but with the latest Intel display drivers installed it works with a number of games. Here's a list of what I have tried so far:

Anarchy Online

Battlefield 1942 (Road to Rome, Secret Weapons of WWII, Vietnam and many other user mods)

Conquest

Ghost Recon

Halo: Combat Evolved

Lord of the Rings: Online (pay to play and I don't anymore)

NeverWinter Nights (Diamond Collection)

Real War

Red Alert: A Path Beyond

Star Wars Galactic Battlegrounds

Unreal Tournament 2003 & 2004

WarSow

Wolfenstein: Enemy Territory

These are just what I have tried. What I would be interested in knowing is what older games you have tried. I am most interested in those that can still be purchased easily in a store. There are a lot of older PCs out there and sometimes games are overlooked because, like movies, they are coming out on a very frequent basis. If I find others I will post a comment with details on my findings. The key is that many older PCs lack support for Textures and Lighting and this support is necessary for many new games.