You know how the jukeboxes in bars now are computerized? Ok, now you know when you purchase something on amazon.com, and itll say "people who purchased this item also purchased the following..." How about a software in the jukebox when you pick the song, a feature would come up with suggestions of other songs to pick based on the genre, popularity, etc.

Bars and jukebox companies would love it because it encourages people to choose more songs. It would be based off people's "other choices" when selecting the same song.