I find myself asking that question now and then when I'm working at off hours.
Our ARTCC has made great use of Gerry Hattendorf's "Aircraft, Airline and Airport Information Decoder" program for Windows. With his permission, I've taken the data and done a very simple re-implementation it for the web. It's still "beta" right now and I'm working on getting some data updates in.
http://www.flightsimtoolbox.com/lookupAny feedback/suggestions/etc are welcomed. Please use the contact info on the bottom of the page if you'd like to contact me.
Mike Burke
ZHU ARTCC Webmaster
http://www.zhuartcc.org