An updated version of PureDarwin nano has been posted. PureDarwin nano is a minimal version of the Darwin 9 OS that boots into a working bash. PureDarwinNano_20091226.tar.bz2 contains a virtual machine for use with VMware (be sure to assign at least 350 MB RAM). It also contains an ISO that can be used on Intel hardware. You can download it here.
The PureDarwin project is continuing to work on a more complete release of PureDarwin.