It seems that we only really need free space collection, and there seems
to be no reason why this can't be fully paralell... It only has issues
when you allocate a long-term item after allocating a ton of transient
stuff... (cuz that pushes out the end of the address space while leaving
a lot of dead room.)

Caompaction might be possible by replacing OOps with a new object called
HOLD that simply captures method sends untill the GC has moved the
memory at which point a "RELEASE" messages are processed... (just a
hair-brained idea...)