Hey,
I'm looking into renting a remote windows desktop... something a bit like Nivio (http://nivio.com/), but with full functionality, rather than a limited user account like Nivio uses.

Does anyone know of any alternative to Nivio?

Cheers,
Scott.

a Windows vps accesible as a online VNC service is not valid for you?
For examplo, if you buy a VPS server managed with SolusVM, you get access in your SolusVM account to connect using a VNC console. Then, your Windows is accesible via Firefox :)