Instead of focusing on Scheme, I started to write a general purpose memory model based on Meroon for the object part. Its name is DMeroon . A related problem is how to support multiple users that may share modules or, more precisely, mutable locations. First-class modules are dealt with in ICFP96 . Luc Moreau and I extended the notion of group with energy.
Computations take energy to proceed and stop when the energy is zero.
A small set of primitives allow to control energy consumption, to transfer energy from one group to another and to be informed when energy is exhausted or when groups are terminated. See our recent report or DSL97 paper. Distributed computing requires to exchange messages or, better, objects. The main idea is to see the serialization as a compilation while the deserializer acts as a byte-code interpreter. I also extended the concept of generic functions to distributed generic functions.