Q is (I believe) the successor to K (KayLanguage) for use with Kdb+ from Kx Systems. It was created by ArthurWhitney, based on K but "providing a more readable, English like interface." (Wikipedia) There is a trial version of the system (appropriate for anything other than production use) available at http://kx.com.
The Q Abridged Manual (http://kx.com/q/d/q.htm) gives a very dense list of examples. Q For Mortals (https://code.kx.com/trac/wiki/QforMortals2/contents - anonymous as username and password) gives the long version.
There's also a functional language called Q that had some academic success. Presently (August 2010), it looks like it hasn't been maintained since sometime in 2008. (http://q-lang.sourceforge.net/)
I think this is the correct WikiWord for the language, but I would be delighted to move it to QqLanguage? concommitant with a lot of whining.