Sysv_ipc gives Python programs access to System V semaphores, shared memory and message queues. Most (all?) Unixes (including OS X) support System V IPC. Windows+Cygwin 1.7 might also work. Sample code is included. sysv_ipc is free software (free as in speech and free as in beer) released under a 3-clause BSD license. Complete licensing information is available in the LICENSE file. You might also be interested in the similar POSIX IPC module at: http://semanchuk.com/philip/posix_ipc/