The acronyms you seek, sir, are play by e-mail (PbEM) or play by mail (PbM). True grognards know this. Not that I am a grognard. But I know one. Or knew one, once. He died when he slipped and fell after throwing his cane at a passing Millenial.5. Aside. Playing in on-line PbP systems, I have to marvel at those who played in snailmail PbP systems.
FIFY.6. Anti-gnomepaladin comments are always welcome. You have to get those ankle-biters before they get you.
Hmmm, I play 1-3 times a week in groups with people I met via LFG boards/Meetup etc - but as a result they have become my friends.