The "special purpose" mouse used with some "high-end" drafting and CAD programs reads (optically) a grid of lines on a special pad. When used within the programs, you have to "zero" the mouse by clicking on diagonally opposite corners of the pad, and it thereafter works as a pure "displacement" input with no acceleration. All of these that I've seen work in other programs, but I can't say with certainty that the acceleration function stays off in Windows programs.

In effect, these mice work much like a stylus pad, in which your "pointing spot" or cursor on the screen follows where you place your "pencil" on the pad. One of these might be a suitable option for you.

The mice I've used most recently, of the type above, were on CADAM and APOLLO systems, but it's rather difficult to get information on equipment or accessories for either of these. AutoCAD and Photoshop (or other "Art" programs) are other places where similar "specials" are sometimes used.

The generic term to look for "unmousy" options would likely be "pointing devices," which will, of course, include the standard mouse.

I'll note that I get significantly different performance on my laptop with a USB connected mouse. The "touch pad," which kept making my cursor fly around when I'd brush it while typing, is connected to the external mouse port, so you can't turn off the touch pad if you use a "normal" external mouse (or trackball), but the USB mouse works independently - with it's own driver, and with it's own rate and acceleration settings. With the external USB mouse plugged in, Windows settings don't affect the mouse. These settings seem to behave differently than the "normal mouse in XP" settings, but I'd have to do some experimenting to see which differences are due to the connection and which are because the USB mouse is an optical.

John