One of KDE's handiest apps, Klipper, works on Ubuntu's gnome desktop!
If you've only worked in Gnome, you might be unaware of a little application called Klipper. It's KDE's answer to the traditional clipboard.
The wonderful integration between applications is one of KDE's strongest features.
Something really cool in KDE 4 is Klipper. It extends the clipboard's functionality by remembering and storing your clipping/copying history.
To put it simply, anytime you copy something to the clipboard, it's saved and becomes selectable for pasting over and over.
To install, open a Terminal and type: sudo apt-get install klipper