As a kid, it's always good to go to birthday parties because you often get free stuff, like cake and balloons and perhaps a wind-up toy or something. As an adult it changes a little, and in some workplaces it is expected that you will be the one to bring in the goodies. This is so unbelievably wrong, but it's OK when, say, record labels celebrate their birthday in this way, as Polyvinyl are doing for their 15th anniversary.
What they are doing to celebrate is making available a free 30-song sampler of their releases over the years, which is very nice of them. You may even discover a couple of bands on it. Listen to it below via SoundCloud, and download it directly from here.
You can also find out about even more stuff that's happening for Polyvinyl's birthday celebrations on a dedicated website.