I have made a little hack of Zenphoto to make it support videos (flash videos actually supported).
My modifications are independant from any theme, it just displays a flash video player when it finds a video ending in .flv
I added a little feature: when you put a video called myVideo.flv in an album and a picture called myVideo.jpg, the pictures is ignored by ZenPhoto and is showed as a thumb of the video.
Well, i think it's all... The demo is here: http://la0c00n.info/zenvideo
I have not seen any topic about this sort of thing in the forum, but if anyone has already done this i apologize :)
Feel free to comment.