Came across this the other day, apologies if this is well known. A British guy made two films about his insecurities with his penis size and I thought they were quite good and to the point. The first one is especially moving since it deals in part with his long time girlfriend's thoughts and feelings about the his size and his attitude towards it.
The first one: My Penis and I on Vimeo
The second: My Penis and Everyone Else's on Vimeo