Glipper is a clipboardmanager for the GNOME Panel. It maintains a history of text copied to the clipboard from which you can choose. You can see this as a GNOME counterpart to KDE's Klipper.
Glipper uses plugins to give the user all the extra functionality they want, including support for Actions, Snippets and No-Paste services.
Also see the sourceforge project page.
Glipper is designed to manage text only, we currently have no plans to manage any other type of data.