[slim19722]

Here's a good write up explaining how Fury Force(SHIELD) became GI Joe with some cool concept art.

Comic Book Urban Legends Revealed #32 - Comics Should Be Good! @ Comic Book ResourcesComics Should Be Good! @ Comic Book Resources

I pretty much mix all my figure lines into one verse. GI Joe and SHIELD are a joint task force operating the Stargate program exploring alternate realities where they may encounter superhumans, aliens, Transformers, post apocalyptic world where zombies(Walking Dead, Resident Evil), or Terminstors while still battling a Cobra/Hydra force.