Mungi
Mungi is the OS project that originally proposed a one global distributed shared memory, aka a single address space or SAS (starting with 64-bit virtual address space).They are trying to build Mungi as a very pure SASOS, that is all data (even the systems') is in the single address space, and no other IPC mechanisms are supported by the OS.
This page is linked from: Off Orthogonal Persistence Sombrero