This panel applet provides an application launcher developed by the fuss project, which uses apt-xapian-index to find applications given a few keywords.

since the index also contains debian package information, keyword search is not limited to the application name and short description provided by desktop files.

you can also drag a file into fuss launcher to see the applications that can open it. fuss launcher also remembers frequently used applications and allows to build a quick-launch list of user favourites.