if you have formatted your c: drive, the situation u describe is impossible.
Actually it's not impossible, just improbable. Using ActiveX (IE only unless you get an extension for it in Firefox) you can get full access to the HD, registry, pretty much anything. Here, test this out.
I'm pretty sure Flash (what Pandora runs on) has the ability to do so as well, regardless of browser (possibly with the help of a Flash plugin like this one). However, I'm not a Flash coder so I can't comment on the specifics, but I do know I have extensions already that create files & folders on my HD, so th