Earliest I've seen was called "Sphincter Lickin Good". Saw it when I worked at msquared productions when me and the video guy there were going through some old tapes looking for something.
http://www.wantedlist.com/DetailList...Title_ID=17959
It was REALLY old black and white, and i remember someone banging some chick in the ass with a huge lightbulb.
Anyone seen anything older? That was from 1926.