This is a cross-post from the Data Logging section but I thought that the people here may be interested.  I hacked together a basic logger to run on Linux using Python and I started a Python library to deal with the low-level KWP2000 communications.

I tried to keep as much of the KWP2000 stuff as possible separated out into the library.  It contains a class with methods to do a slow-0x11 init and a few different read and write methods.

It it by no means a reference implementation, rather, a hobby-quality attempt at a minimal subset of ME7 KWP2000.

Here's the Nefmoto post for the logger, with more info:
http://nefariousmotorsports.com/forum/index.php?topic=4212.0title=

Here's the github link to the logger and library:
https://github.com/trichard3000/mmll

Have fun!