ClipX -- very good (free) clipboard extender for Windows
I've been trialling ClipMate (clipboard extender) but I've just found a freeware alternative that has all that I need. It's called ClipX. It's unfortunately limited to 1000 clips (wish I could adjust this to be unlimited). But the good thing about it is that it has incremental search. So I just press Ctrl+Alt+V and start typing a few letters from the clipboard entry I'm looking for.
Other clipboard extenders have been found lacking. ClipMate itself seems to only incrementally search the clip titles rather than the whole clip. CLCL is lacking search functionality if I'm not mistaken. Ditto is fantastic but slows to a crawl after a while (perhaps unlimited clips isn't such a great idea). Yankee Clipper has a 200 clip limit and no incremental search. etc. etc.
So I'm going with ClipX for now.