KnowPlay, http://www.kplay.cc/ is a useful search site which allows search across multiple search sites/ engines like Google, AltaVista, Ask, About, etc.
Another good feature of the site is that it allows for various types of search, be it Web Search, be it Reference Search, be it Media Search, be it People Search, etc. To add to it, under each different search, different parameters or options could be specfied to get the desired specific result. One such example of Reference Search is shown in the image below.
A very handy site for use.