ClipX is yet another Windows clipboard manager.
I've been using it for a while now, to gather links for my blog posts, and it works quite well.
ClipX has a plugin mechanism to allow the addition of new facilities.
The two I'm using are "Stickies", which lets you keep some predefined text in the list and "Dislog", which stores your entire history on disk, so it's available in the long term.
A number of hotkeys are available. In particular, Ctrl+Shift+V pops up the clipboard history next to the mouse cursor, saving you having to navigate down to the toolbar icon, and Ctrl+Shift+G takes whatever is in the paste buffer and looks it up in Google.
All up, it's a nice simple program, with just the right features to make it useful.