Before Sony's "Spider-Man 3" halted the franchise's momentum, director Sam Raimi had already begun work on "Spider-Man 4," a followup that would have boasted classic Spidey villains Vulture and Mysterio. Unfortunately, the film never came to fruition, but parts of the planning process have survived.
Illustrator and writer Jeffrey Henderson has released several pieces of unused concept art from the film on his website. The pieces reveal a handful of key scenes, like a high-flying fight between Spider-Man and the Vulture and the apprehension of Mysterio. You can check out several images below and a larger gallery on his blog.