To be really snazzy, you could write a batch file utilizing Microsoft's
DevCon utility (it's a Command Line utility alternative to Device Manager) to enable/disable the device, then place a shortcut to your batch file/s in your Start Menu, then assign a 'shortcut key' (e.g. Ctrl+Alt+S) to your shortcut (go to the shortcut's properties page, Shortcut tab).
The reason I said to put it on the Start menu is coz shortcut keys only actually work for shortcuts in the Start menu.
Anyway, that would be the cool techie's way to do it....if someone knows of a freeware application that'll allow you to avoid writing a (relatively simple) batch file or two, all the better.