I posted a little while ago about DVBLogics TVSource for DVBlink and have to say the team over there are coming along leaps and bounds with this. If you don’t know the DVBLink technology acts as a bridge to allow a number of sources (for example IP TV) to be fed into media center as though they are Satellite tuners. Their TVsource allows a number of tuners to be used in this way including many not directly supported by Media Center (DVB-C tuners for example).
One other neat thing is as this is acts as a Satellite source in Media Center you can have 4 of these in addition to 4 terrestrial tuners. As the DVBLogic TV Source tuners can be terrestrial as well that gives a potential of having 8 tuners!
Head over to www.dvblogic.com for more details