ICFP '06 universal machine ported to Factor

Gavin Harrison has written a Factor implementation of the ICFP 2006 contest program. A bit late for the competition, but still fun :-) This is a bytecode interpreter for a simple instruction set. You can find the code in apps/icfp-2006/icfp-2006.factor. It runs quite slowly, but that's a good thing -- it gives me yet another computationally-heavy benchmark to measure compiler improvements against.