Concurrency-type things around and about

Concurrent and Parallel Languages

Erlang
A functional, asynchronous message passing language. Capable of supporting tens of thousands of lightweight processes, Erlang is widely used in telecommunications, and also the implementation language of ejabberd, a popular Jabber server.
occam-pi
Occam is based on the CSP algebra. Largely static, occam-pi adds dynamic data structures and mobile processes; capable of running on tiny platforms using the Transterpreter.
Mozart / Oz
Oz combins declarative programming, object-oriented programming, constraint programming, and concurrency in a single, coherent language. Avaialble for Unix, Windows, and MacOS X.
Inferno / Plan 9 (Wikipedia)
Out of Bell Labs, Plan-9 is a modular, concurrent operating system.
SR
SR stands for Synchronizing Resources, and was originally developed for teaching concurrency. Only available for a variety of Unixes.
E (Wikipedia)
A distributed, purely object-oriented language with security as a focus.

occam Compilers

8/42
experimental compilers developed by the Transterpreter folks. Hopefully one day in the not so distant future these will be become a basis for the main compiler used by the Transterpreter project. For the current state of the compiler, see the 42 pages on this wiki.
KRoC
probably the most actively developed occam compiler. The Transterpreter currently uses the compiler from this project.
http://www.cs.kent.ac.uk/projects/ofa/kroc/
SPOC
compiles occam programs through the use of C as an intermediary language. Has not been in development since 1997.
http://www.hpcc.ecs.soton.ac.uk/software/spoc/
Note: Put it a link to our modified version of spoc.
ACK
the Amsterdam Compiler Kit (by Tanenbaum et al, originally used by minix) has an occam1 compiler. We have never tested it.
http://tack.sourceforge.net/
uOCCAM
A "CS3 Individual Programming Project" at the the University of Edinburgh
http://homepages.inf.ed.ac.uk/stark/ipp/html/index.html
Grid occam
An occam compiler written in Java targeting the .NET platform.
http://www.grid-occam.org/
INMOS compilers
Source for the original INMOS compilers are available. These are probably only of historic interest.
http://www.wotug.org/occam/compilers/inmos/index.shtml