OMG. YOU GUYS. I'm reading what has to be the freaking best AU SG-1 series I have ever read. It has Sam whumping like whoa, but it also has Sam being awesome, Sam/Teal'c friendship, and time travel. Also, one of the most unlikely (but fantastic) 'ships ever. And OCs that I actually like.
It's "The Way..." series by sbz. Apocafic at its finest. (And this apocalypse is an apocalypse.)