8. X10

IBM Research is developing X10, a language designed specifically for modern parallel architectures, with the goal of increasing developer productivity 10 times.

X10 handles concurrency using the partitioned global address space programming model. Code and data are separated into units and distributed across one or more places.

X10 code is similar to that of Java. The X10 compiler can output C++ or Java source code.

The compiler and runtime are available for various platforms, including Linux, Mac OS X, and Windows. Additional tools include an Eclipse-based IDE and a debugger, all distributed under the Eclipse Public License.

9. haXe

haXe is a multiplatform language that can target diverse operating environments, ranging from native binaries to interpreters and virtual machines.

Developers can write programs in haXe, and then compile them into object code, JavaScript, PHP, Flash/ActionScript, or NekoVM bytecode today.

The haXe syntax is C-like, with a rich feature set. Its chief advantage is that it negates problems inherent in each of the platforms it targets. For example, haXe has strict typing where JavaScript does not; it adds generics and type inference to ActionScript.

Although still under development, haXe is used commercially by its creator, the gaming studio Motion Twin, so it's no toy. It's available for Linux, Mac OS X, and Windows under a combination of open source licenses.