Oz is a MultiParadigmProgrammingLanguage supporting ConstraintProgramming. The book ConceptsTechniquesAndModelsOfComputerProgramming uses Oz to teach programming. The web site is http://www.mozart-oz.org/
OzLanguage is in some ways inspired by ActorLanguages.
Oz is a really slick language that suffers from being way too academic. It's got some awesome ConstraintProgramming features, but unfortunately, it doesn't really talk to the rest of the world. :/
It has a CeePlusPlus ForeignFunctionInterface, networking libraries, etc. What more do you want? On the "too academic" point, see <http://www.cs.utexas.edu/users/EWD/transcriptions/EWD06xx/EWD611.html>.
It also suffers from having an implementation that's tightly coupled with EmacsEditor. Anyone not an Emacs user is going to stay away.
The MozartProgrammingSystem development environment is somewhat dependent on EmacsEditor, but the compiler, VirtualMachine, etc. are not.
I've been playing around with Oz for about a month, and quite like it. The base language encourages declarative and functional styles of programming, but the extended language supports many different paradigms, including ObjectOrientedProgramming.
Too academic? Commercial software development could stand to learn a bit more from academia, without a doubt, and vice versa. I almost wish I'd learned to program by starting with a language with the formal rigor of Oz. -- DanMuller
I'll try the "academic" language, as a programming toy, have fun! -- David Y2
See also Mozart programming environment MozartProgrammingSystem.