Hi... I need to run my T3i on AC power during an all day green screen shoot and I looked at the canon made ACK-E8 which would help me do just that for around $65. I was wondering if anyone makes a good battery grip that can also have an AC cable plugged into it and run the camera on AC power? It seems that since the grip would be plugged into the camera through the battery interface, it would be pretty simple to have that option available as well. I really would like a battery grip and I figured if I am going to drop $65 i may could find something like this for the same price or a little more in order to kill two bird with one stone. Suggestions? Thanks so much!