Launchy is as cheap as free (as in free beer), and it indexes all the filetypes you want, and with a hotkey like alt+space or win+space it learns by usage, so y

Launchy is as cheap as free (as in free beer), and it indexes all the filetypes you want, and with a hotkey like alt+space or win+space it learns by usage, so you end up just typing one or two letters... plus there are plug-ins