The people at Atanar Technologies have been able to create a stunning streaming service of classical live concerts - not requiring a particularly fat pipe at all. It's called Medici.tv and has some wonderful (live) content. Check out this Berliner Philharmoniker concert under Simon Rattle: Tchaikovsky's Nutcracker, the 'Rakh 3' (with Yefim Bronfman) and a Sacre in the rain.
(Have you seen the Grooveshark player in the right hand column of this blog? Poor guys have been sued!)