Maybe this one isn´t new to You but it was to me!
When using Miglia's AlchemyTV DVR PCI along with an installation of iChat USB CAM 2.0.2, Apple´s iChat AV is able to stream any TV signal into the video chat window. This one requires lots of bandwidth (tested with 2 MBit), but it can be quite fun -- show TV to your friends around the world, or if you need a special broadcast from TV stations as a live stream.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20040930063046220