I took a whack at this 9 years ago. My code's at http://wry.me/~darius/software/idel http://wry.me/~darius/software/idel and there were other, probably worthier

I took a whack at this 9 years ago. My code's at http://wry.me/~darius/software/idel http://wry.me/~darius/software/idel and there were other, probably worthier, attempts around the same time and before, like Michael Franz's work with Oberon. Basically: make a low-level VM more or less like LLVM without the machine-dependent semantics and with a compact, easy-to-verify wire format. Apparently PNaCl is working on fixing those infelicities now, or at least the machine dependence. (I had some fun but decided the obstacles to addoption were too great and we'd end up with x86 in the browser someday. So the NaCl announcement years later amused and gratified me.)