TheBUFVC (Brittish Universites Film and Video Council) have just released their new federated search environment. It is currently in beta and the multi-purpose search engine and interface will eventually be released under an open source licence.
To quote from the BUFVC website http://bufvc.ac.uk/federatedsearch
"Now users can search all collections from a single entry point and easily view collated results through a clean design and innovative use of icons. Users from HE/FE institutions and BUFVC members only need to login once to access more online content. Advanced users still have the option to search one database at a time using detailed search features."
The project can be accesed here: http://beta.bufvc.ac.uk/