SimPy is a process-based discrete-event simulation language based on standard ["Python"] and released under the GNU LGPL.
It provides the modeller with components of a simulation model. These include processes, for active components like customers, messages, and vehicles, and resources, for passive components that form limited capacity congestion points like servers, checkout counters, and tunnels. It also provides monitor variables to aid in gathering statistics.
The current version is 1.7.1 (released in June 2006).
More information can be obtained from the SimPy [http://simpy.sourceforge.net/index.html Homepage].
There is also a [http://www.mcs.vuw.ac.nz/cgi-bin/wiki/SimPy SimPy Wiki] where developers and users discuss SimPy.