Here's a great little commercial featuring Nathan Fillion and Robert Downey Jr. promoting their two latest projects The Avengers and Castle. What's cool about this ad is that in some strange way Fillion has crossed over into the Marvel universe, which is something we'd all really love to see! We know over the years there's been a ton of talk about Fillion playing Ant-Man, but nothing has ever happened with that. It's just a fanboy wish that we hope one day comes true. It would be so cool to see these two characters interact with each other in a Marvel film! If Fillion doesn't ever get the role of Ant-Man what other Marvel character would you like to see him play?