Project Opus has long been one of my favourite music communities. It's Vancouver-developed, and though the scope of the site isn't limited to Vancouver at all, there's a bit of an emphasis on local music just by default.
The developers have just released Mixx, a very clever Facebook app that allows you to not just make typical playlists of your favourite songs, but request songs from friends based on themes: "I want music that will wake me up in the morning", "I want music that makes the rain go away", and so on. It's quite legal, because although you're uploading an mp3 to the site, it can only be heard by your friends and they can't download it - basically as if they were hanging out at your place and you had it playing on your stereo.
I like this concept a lot, because I find the only times I get into new music is when a friend recommends it and I look it up. This skips the "looking it up" step altogether.
It's an addictive little app - I had to force myself to go to bed the other night when I was having too much fun putting together a Mixx of music that I was finding particularily resonant (starting with "Go Slowly" by Radiohead). There'll be more where that came from. Do check it out.
Kirsten Starcher lives in Vancouver, BC, spending half her time as a musician, playing bass in ARCTIC as well as solo, and the other half as a web designer/developer.
You can contact her at "kirsten at crowstoburnaby dot com" (turn it into a proper email address, of course!).