Fast Find Menu – http://www.webappers.com
jdMenu Hierarchical Menu – http://jdsharp.us/jQuery/plugins/jdMenu/
Perciformes – http://www.matthewjrichards.co.uk
idYabs menu – http://www.sunsean.com/idTabs/
LavaLamp – http://gmarwaha.com/blog/?p=7
Context menu – http://www.trendskitchens.co.nz/jquery/contextmenu/
Dock Menu – http://www.ndesign-studio.com/blog/mac/css-dock-menu
Pop up menu – http://webexpose.org

More, more, more…
http://www.sastgroup.com/jquery/240-plugins-jquery