I was actually thinking more along the lines of Dolby, DTS, THX, etc. trailers but if while we're at it, normal trailers would be great. My dream would be the original theatrical trailer for Pearl Harbor with the music from the Thin Red Line. It was never released on any format.
http://www.youtube.com/watch?v=oqeitdH5FX0
I've got the DTS trailer disc with the audio on it somewhere. Getting a better picture would be a little bit more of a problem.