Shame the author promotes the use of Spotify so much, for two reasons: - the ridiculous amount of money going to artists (i.e. the ones who do want money for their music), although you could argue that you would generate revenue for every play the song gets, rather than a one-off amount when buying it (although, pretty sure it still doesn't compare); - having Spotify means everyone will ask you to play your favourite song, and you'll have less of an excuse not to, which is a massive PITA.

Contrary to what the article says, Mixxx is cross-platform (GNU/Linux, Mac, Windows). I really recommend that amazing piece of Free Software. It is the only DJing software I use.