Here's an idea I had for Loki that I suggested over on the Avengers boards: See, I thought I had a good way for Loki to fit into the story for The Avengers back when Thor was set during the time of the Vikings and ended with [BLACKOUT]Loki hiding out in Midgard[/BLACKOUT]. I figured he could pop up briefly in Iron Man 2, unnamed, maybe as some kind of shady businessman on Justin Hammer's board of directors, or maybe as an associate of Stark's father. And in Captain America, he pops up - again briefly, again unnamed - as an influential Nazi who helps establish the Red Skull. Just create the sense that Loki has been popping up at various points in history, never looking a day older, messing with the lives of the different Avengers in different ways. Like an evil version of Richard Alpert from Lost. But I don't think that idea would work anymore, seeing that Thor will now be set in the present, apparently.