While I love a pretty minimal desktop (how minimal depends a bit on my mood, see the tint2 in my screenshot), sometimes I forget about apps I wanted to try. That's where a menu comes in handy. This is one. You can just bind it to a key and it searches the XDG menus for your applications and opens a menu.
Get it via git:
git clone http://mad.unserver.de/REPOS/xmenud.git
It needs pygtk and pyxdg. Try
xmenud.py --help for options.