Hi everyone. I know that my vote is late, but I think I can answer the question stated in the subject of this thread, from my perspective, at any rate.
I'd like a short campaine, or even a single adventure where the players from a regular D&D setting are hurled forward to our present time for a mission, or some such. I'm talking about a world were the ties to the past, though lost in myth, still exist. If the players really wanted to do some reasearch, they may even find references to themselves.
Perhaps the gods of magic pick the group to reistablish their rein in the future, and need the characters to 'do' something in order to open the link to magic once more, or some such thing.
I'd like to see all the complications of a primitive, savage group coming to the law choked world of today and see how they fair.
This is trully an adventure that I would be drewling to join, especially if it turned out to be well done.