FunOS
Proposal for LISP oriented OS based on Assembly, Caml, FunScheme, a Scheme variant of LISP language.
http://www.sarg.ryerson.ca/~cmwilson/code/funos/funos.html
SPIN
Dynamically extensible, Exokernel-based, provides many core services: scheduler, kernel threads, domains, event dispatcher, security mechanisms, primitive VM operations. Blurs distinction between kernels and applications, which traditionally live in user-level address spaces, separated from kernel resources and services by an expensive protection boundary. Lets applications specialize the kernel by dynamically linking new code into running systems.
http://www.cs.washington.edu/research/projects/spin/www/