If you are a DJ you should look into this.
Beatport Link allows you to mix your own collection and create your own playlists using their software. This seems like it would make life way easier for DJs. First off, they have over 6 million songs ready in there "performance software." This allows you to make mixes BEFORE purchasing the tracks. The tracks can also be played in the club with no internet connection. I never knew DJs needed a internet connection to even begin with.
Beatport CEO, Robb McDaniels, said: “At present, most DJs can’t easily stream music directly into a club set-up. With our offline locker technology, laptop DJs can now store tracks offline to play without worrying about Wi-Fi.