The Revenge of Shinobi (1989)
Included here as one of Spidey's finest cameos, Revenge of Shinboi appeared on the Sega Mega Drive as a sort of sequel to the successful arcade game (it's also now available on Wii VC). What's this got to do with Spidey? Well in the first version he was one of your chief enemies (amongst others including Godzilla, the Terminator and er Rambo, there was a shapeshifting thing going on). By the second version Spidey remained but transformed into the devil once defeated. In the third, Spidey was welcomed in as an officially licensed character. Quite bonkers but certainly one of the best guest star appearances ever.