This isn't a virtual PC or even a remote desktop, this is one of those DHTML/AJAX browser-based pseudo-desktops that can only run applications (usually web applets, sometimes remotely hosted AJAX apps) that the hosting system pre-installs. There's actually quite a lot of these around now. I've signed up for several at various times, but they're all so useless that I've stopped using any of them. The most recent one I tried was Jooce but it was no better than the rest. Here's some names to google: Jooce, Goowy, XINdesk, OODesk, Orca, craythur, desktoptwo, eyeos, glide, purefect, ssoe, YouOS, astranos, bedesk, cmyos, doxboard, glide, mygoya, oos, parakey, psych, startforce, webdesk, webdows, zimdesk, fenestela, zkdesktop.
Best solution: get yourself a 24x7 net connection and allow remote access to your home system. (ssh, VLC, or Remote Desktop) All the comforts of home and the convenience of accessing it from anywhere on the net, and you don't need to entrust someone else with your data.