Search an Android RAM dump for Linux dm-crypt (incl. LUKS/cryptsetup) keys. 95% based on Torbjörn Pettersson's code.
Very much a hackjob, not guaranteed to work reliably across multiple versions or host platforms, etc. I was happy with the LiME module for acquiring the RAM image.
See my blog post for information on some informal research I did about recovering crypto keys.