Copying and pasting between Emacs and other Linux apps

Copy to Emacs clipboard with:
Ctrl-[Space] : Set marker (start/stop)
Alt-[W] : Copy to Clipboard
Ctrl-[W] : Kill to Clipboard (cuts from original position and places it in clipboard)
Ctrl-[Y] : Yank or Paste at current position from Emacs Clipboard

[Middle Mouse Click] – Paste in Another Application from Emacs Clipboard