Your link goes to a flash-based embedded player. One reason these players have become popular recently is that the actual data url can be embedded inside the player itself, making it very difficult to access externally.
There are ways to access the streams for many of the big sites like youtube, but since each site and player has to be specifically coded for I doubt there's anything that's been programmed to extract this one. Besides, this is a continual "live" stream, not just a static recording, so it would probably be even more difficult to work with.
Probably the best you can do is find some way to record the playing audio directly from your sound card.