Well, i use it sometimes. But not on PC, but on my mobile phone. I have some software called "mobbler" in the phone which streams up music from last.fm. It's great and the most useful mobile application for me.
wanted to bump this up. Still use last.fm, just to track and log the music I'm listening to. for online streaming, i use grooveshark - they have very decent quality audio
Recently stumbled acrossFree Music Online - Internet Radio - Jango, and hooked ever since.. Decent sound quality and almost no ads, one of the best online Radios I've come across.. And yes they've got a pretty decent playlist too
Yes..I have my account signed up in US and it works here with a charm..You will be amazed by its features.It is the ultimate music service.Even I have installed Spotify in my laptop, Squeezebox Touch & and Iphone also..Even you can use its airplay function to enjoy on AVR with network facility.. https://www.spotify.com/int/
Login with the details of account signed up abroad and you can enjoy it here..