Is there a way to enable some kind of stereo cross-feed like a stereophonic-to-binaural filter to listen to music with headphones on my computer?

After some googling I found some interesting projects/software like bs2b ( which is available on the Precise repositories, but I have no idea how to plug it into pulseaudio, any ideas?

Bonus question: there is any free software capable of converting a 5.1 stereo surround input into 3d binaural (sometimes called virtual surround) for headphones?