Could be a good addition to WME. Don't know if it's widely apparent but the XBox360 wired controller is XP and Vista compatible (it has a USB connection). Looks like it's on the way to becoming the standard controller for PC gamers. Even though I don't have an XBox I got one of its controllers and it works great. It's not that expensive either.
Microsoft have an XP driver for the controller downloadable from their site. I had some issues with it on some games but I haven't checked back in a while and I'm sure there will be regular updates as soon as Vista comes along.
I'm currently using an alternative driver called XBCD (
http://www.redcl0ud.com/xbcd.html).
There is even a way to convert existing games for use with any controller using a tool called ControlMK (
http://www.redcl0ud.com/controlmk/). It allows you to map keyboard keys to the controller. You might need to restart ControlMK to make changes take effect but your games should play on the controller once you have it configured (you'll probably have to play around with the settings, such as