Haskell, Ocaml, and Scala? All are open languages, cross platform, and first two at least are Free. And Scala runs on both the JVM and .NET, covering all three platforms. Is that what you meant?
Haskell and the ml family only have ease-of-use for people who think higher order predicate calculi have ease-of-use - some of whom will vigorously argue that everyone should find them easy-to-use.
(I don't know enough scala to form a judgment, but I haven't heard it being touted as primarily having ease-of-use, in contrast to Python and Ruby.)
http://stackoverflow.com/questions/2987408/actors-in-scala-n...
There's only 1 guy working on it but he's been going at it furiously
http://lamp.epfl.ch/~magarcia/ScalaCompilerCornerReloaded/
(do they feel itchy about using the LAMP subdomain?
I think it has been decided that the JVM will always be the LCDenominator VM (e.g. implmentations on other VM's pretend type erasure is happening, for compatibility with JVM implementation)
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