My first exposure to Madonna* was the song "Like a Virgin", which I still hate to this day. But I quickly warmed up to Madonna herself in subsequent years and songs, even though Madonna herself has turned out to be, well, a tad weird. Anyhoo, my favorite song of hers is the little bubble-gum confection "True Blue", which is as perfect a pop song as I've ever heard. Madonna's voice was somehow perfectly suited to this tune -- and its exclusion from Madonna's Immaculate Collection greatest hits album still annoys me. (I later got the song during my three-week experiment with file-sharing a few years back.)
Anyway, in the mid-80s, when "True Blue" came along, music-video was the name of the game, and every major single had a video made for it to air on MTV. What was different about "True Blue" was that before Madonna made her own video, MTV held a "Make Your Own Video" contest, with "True Blue" as the song. They played a lot of the entries during a marathon one day (just about all of them sucked), but the winning amateur video was actually pretty good. It can be seen here, albeit with pretty crappy video quality. Madonna's eventual "official" video for the song can be seen here, but for me, the amateur one will always be the superior version.
* Yes, I realize that referring to one's "exposure" to Madonna is a troublesome metaphor. Oh well.