I haven't seen this anywhere else, and although I'm not sure whether to put this here or in the VM services section (it does refer to the 50MB service though...).
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We want to say a big, loud thank you for being a valued 50Mb customer by giving you Spotify Premium free for 3 months when you sign up to our super fast up to 50Mb broadband for another 12 months.
Imagine having access to over 13 million music tracks and albums with no interruptions - for free. Cool or what?
With Spotify Premium you can search for any song or album you like and then play it straightaway without having to download it. And even better, because you don't have to listen to any adverts, you can just enjoy getting lost in the music.
http://shop.virginmedia.com/existing.../spotify1.html
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The link then goes on to say that after the 3 months are up users will be automatically put onto the Spotify Free offering, which has some restrictions.
I currently use Grooveshark, but this might tempt me. I just need to find out more about the offline mode.