So spotify made a great html5 player for their service: https://play.spotify.com But they forgot their encription... NICE! :)
!!!!!!!!!!!!DISCLAIMER!!!!!!!!!!!!!!
Hey I don't like encription but love spotify, just pay them for your content and I am sure they fix it soon ( like create a corrupted mp3 and fix it with the html5 file api ).
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Install the extension
https://chrome.google.com/webstore/detail/downloadify/femggkppepeoihnolcfenmkfgekffihm
Go to https://play.spotify.com play a song and watch your download folder!