You guys are probably already all over this one, but it's worth a post here on the blog [Thanks Tom]. This may not be true HDR for the super technical term, but this new feature in Magic Lantern provides a higher dynamic range between shadows and highlights. Multiple exposures, a bit of post work, and interpolated frames, there's more details on work flow and which cameras are supported at the video link: https://vimeo.com/33987353.