Does anyone know of a simple way to swap whatever is currently in my clipboard with the current mouse selection?
So lets say my clipboard has the text Foo
No generic solution for this exists, so sorry: I anticipate disappointment.
You might be able to build a Visual Studio plugin with an implementation of this, but it isn't a standard solution on any platform besides maybe Vi/Vim or Emacs (and even then I'm not sure).
I know you didn't want a solution that involved installing anything, but I landed on this page with the same question, so I decided to post an answer ( that does include a gui )
install AutoHotKey!
see http://www.autohotkey.com/board/topic/15-clipboard-hotkey-functions/
Kind regards
Ward