They've tackled the problem of sending signed, encrypted code around. Check out Grail , their web browser that supports applets. Caml Special Light MMM is a web browser written using this ML dialect. The GUI is Tk-based. Obliq objects have state and are local to a site.
Obliq computations can roam over the network, while maintaining network connections.
Non-commercial use license. Alan Kay's group. ANDF Architecture Neutral Distribution Format. Another mobile code technology based on parse trees rather than opcodes. The following technologies are related and interesting, but they don't appear to be available on the net.