A new development snapshot of Mini vMac for all your emulating needs:http://minivmac.sourceforge.net/
"The latest Development source snapshot has an intial merge of Mike Fort's LocalTalk emulation. It is enabled with the build system option "-lt". It is currently implemented with an alternate version of one source file (SCCEMDEV.c), but I expect to eventually merge that with the original. I've already editted it quite a ways in that direction, hopefully not adding too many bugs.
The are currently some limitations. It is only implemented for OS X. It requires running the command "sudo chmod ugo+rw /dev/bpf*" to allow Mini vMac (and everyone else) access to all network traffic. It loses packets some of the time. If running faster than 1x, it loses more packets (which in a way is good, as that should be a clue where to look for the problem). So the "-lt" option causes the default speed to be 1x. The "-lt" option also cause Mini vMac to run in the background by default, because Mini vMac can't be a proper LocalTalk node if it isn't running. And you need to manually turn on AppleTalk in the chooser - I can set the PRAM flags to boot with AppleTalk already on, but it doesn't work properly.
All my testing of Mini vMac with LocalTalk emulation has been done in VMware Fusion 4 (sponsored by Peter Godwin and Andrew Macfarlane), which now supports running OS X as guest.
In other news, I've verified that the version of Mini vMac compiled in PC-BSD 9, with the new "-t fbsd" option, works in FreeBSD 9, and also FreeBSD 7."