I've been working on a related concept, but more along the lines of developing a low-level IR (LLIR) and corresponding syntax that allows direct coding in the LLIR. It would essentially be a portable assembly language. The LLIR could be then be compiled down to machine code for different architectures, or even run directly in a VM.

This isn't too different from the LLVM concept, except the IR would be a practical programming language, much like assembly. Furthermore, the IR would provide access control primitives (reference capabilities) that most languages do not support, but that are extremely useful for low-overhead secure computing and concurrent computing. These primitives could be especially useful in the design of exokernel OS's, and related applications.