Rusalka Virtual Machine
The Rusalka VM is a small personal project of mine to implement a fairly simple register-based process virtual machine.
Rusalka is implemented in C++11. Currently, it supports
Once the Rusalka language is fleshed out and implemented on top of the Rusalka VM, there will likely be more to say about what it does and does not support, but for now it’s a fairly bare-bones virtual machine. The upside is that it’s fairly easy to produce bytecode for or to compile to Rusalka assembly.
In all likelihood, Rusalka assembly will be abandoned as a core part of the VM, as it’s only in there for testing at the moment and building an assembler into the VM probably isn’t a great use of resources.
Finally, if you want to read a lot of very dry writing about Rusalka’s design and implementation, see my blog post over on Spifftastic: http://spifftastic.net/post/2014/07/on-the-rusalka-virtual-machine/. 
If you want to contribute to Rusalka’s development, it’s simplest to create a patch and submit it via a pull request on Rusalka’s GitHub repository. Please include a decent explanation of your changes to help folks read them (i.e., walk me through why you made the change, what it does, etc.).