I've seen the Red Rocks and Albert Hall DVD concerts but here is one I stumbled on from Youtube called "Live from the Isle of Wight" from 1970.
It's not a straight concert, more a documentary but if you are a fan I think you will enjoy it. Remember, it was recorded in 1970 so don't get you hopes up for top video and audio quality but I thought it was pretty good.
A little over an hour long and streamed it iMac>Apple TV>60" Plasma with no problems.
http://www.youtube.com/watch?v=vRuMgs4b1qk