Intel GMA
Like some others, my Intel "82915G/GV/910GL Express Chipset Family" onboard graphics doesn't work at all for shaders. I've got Direct 9c.
The menu doesn't accept the shader value of 1 (it just resets to 0 when I look at the menu again), the shortcut appears to be ignored and even hacking the default.cfg in Notepad doesn't work (resets to 0).
On a positive note, I couldn't get multiplayer to work properly in 2.n - the action kept freezing (i.e. I couldn't rotate the camera at all or select joints on my go) and now it works fine - I think this is because I selected Frame Skipping - not sure.