I have an idea for getting young Severus into the future after Snape dies in the Shrieking Shack. I think it belongs to one of my plot bunnies though. The one where Ginny marries Harry to help him with a Potter family thing. The story starts when she's leaving him per their agreement and he's waiting to see what hits him.
Wow is that pretty vague. It makes sense in my head though. *g*