Scuttle is php/mysql based script, and allows you to run own del.icio.us like service. Script features: store, share, tag, watchlist, user profiles and much more capeabilities.

I could not find online demo yet, so you can check screenshots here: http://sourceforge.net/project/screenshots.php?group_id=134378

and get it here: http://sourceforge.net/project/showfiles.php?group_id=134378

Good Luck