I am looking for renting virtual machines for testing my desktop software. In particular, I am interested in all modern Windows client versions (XP no SP, SP1, SP2, SP3, Vista with/without SP1/2, Windows 7), also a couple of Linux distros and of course a MacOS X - but that's hardly possible. There are plenty of virtual servers for rent but they're all running Windows Servers of different kinds, and I need XP's and Vista's. Of course I can do that locally but this requires building the infrastructure and buying licenses, which takes time & money. So any pointers here?
EDIT: Found VMBed.com but they only offer XP and not Vistas - but already better than nothing.
EDIT2: Was pointed to BrowserCam - will try them out and post here, for now they look promising but a very ugly website.