Just a thought, but as I am running my laptop on Ubuntu, if I do a Ctrl+C, it remains in the clipboard memory whilst the application that it was copied from is alive. When I shut that app, the clipboard is cleared. There could be a setting somewhere that allows it to be retained after the app is shut, but I'm really not that bothered about this. Perhaps that is where Ubuntu wins on the memory front, the memory an app uses is cleared when shut.
That may also go some-way into explaining why Windoze is constantly reading/writing to it's pagefile.
In short, if Firefox has some text copied from it, I can post it here.