OK I just ordered one Hauppauge HD PVR 2 http://www.amazon.co.uk/Hauppauge-Gaming-Edition-Capture-Device/dp/tech-data/B0092P47GW/ref=de_a_smtd And a light bulb just lit in my head. I have the Canon T2i and T3i If I can make the Hauppauge portable could I plug it into a laptop and use it as a portable recorder. That is if my son lets me borrow his Christmas present.
That device still records video to H264, so you won't be any better off than recording on the camera. The advantage of external recorders like the Atomos Ninja is recording to uncompressed formats such as Prores.
"Recording datarate: from 1 to 13.5 Mbits/sec"
well.... canons encoder does more :)
but it litteraly would work? in the description of the HpPVR2 Gaming Edition is written that the hdmi-signal has to be "unprotected" like on an xbox360s hdmi-out.