I don't think this has been posted before.
On their Kill Rock Stars web site, Deerhoof are offering up free downloads of their collection of oddities and outtakes album, Various Songs[MP3s]. It includes a mash up of Deerhoof and Swizz Beats that was discovered and sent in by a fan...
Deerhoof/Swizz Beats Mash up [MP3]
http://deerhoof.killrockstars.com/