Or actually, if there's some way to pop up an account impersonation dialog
that is NOT the UAC dialog, that might suffice (basically, there's some bug
in UAC that is preventing it from showing me any admin accounts when it
prompts for admin credentials...seriously, I've been locked out of
everything from reinstalling the OS to debugging ASP.Net apps to installing
anti-virus software)
And just my luck, the UAC blog is now shut down

I've spent 2 hours
talking to Microsoft trying to explain to them that using their own
keyboard, you can get locked out of the OS...all because the UAC dialog
won't give me a damn password box!