[nialo]

mostly curiosity: why a stack vm in particular? (is it because you then need to write the compiler for it?)

[tptacek]

Because if you're familiar with conventional real register architectures, the stack VM forces you to rethink it, in a much simpler way. It's a useful simplifying abstraction.

[vram22]

There used to be a lot of interest in, and articles about, stack machines (real ones, not VMs) back in the days of mags like BYTE and PC Mag. Good reading.