An interesting piece of software I've run across at Macworld | iWorld 2012 is Audible Magic, automated-content recognition software that relies on digital fingerprinting. The Audible Magic technology will identify a TV series based off the audio as it's being broadcast. Audible Magic's customers include yap.tv and Miso, which will have the Audible Magic's recognition integrated into their apps.
Check out the video as Audible Magic's Jay Friedman gives a demonstration of the software and explains how it helps viewers.
Yahoo's IntoNow offers a similar feature, including for live sports or news.