Here are two featurette videos for the upcoming The Amazing Spider-Man 2 fim.
The Avengers: Age of Ultron - Teaser Trailer
Marvel have released the first trailer for The Avengers: Age of Ultron.
Guardians of the Galaxy - Making of VFX
fxguide have posted a massive article on the VFX of Guardians of the Galaxy.
Marvel - Fan Animation
BlackMeal has created a short animation meant as homage to the characters of the Marvel universe.