Maybe things have changed, but when I was in Canada I had never heard of Spotify. We were all still downloading things on iTunes or, more often, illegally on Limewire. Everyone in the UK listens to music on Spotify.
You simply create a free account and download a bit of software, which allows you to search and then listen to full tracks of music on your computer. It's super fast, there's tonnes of music on there (even indie stuff), no risk of viruses and it is completely legal and supported by the occasional advertisement. Unlike Last FM, you can listen to tracks you like over and over again and even create play lists. It can also function as a radio station if you want your music selected for you based on some parameters about what you want to hear. Otherwise you are free to choose from their huge library of music and listen to whatever you want.
The only downside is that the music doesn't belong to you, so you can't download it or make Cd's for your friends (though you can share play lists) and you can't load it onto your iPod. You also need the internet to run it.
Go and set up your account and let me know so we can share music. Now!