I thought I'd relax a little after my previous post and do something a bit nostalgic and fun. Here, for your idea-inspiring pleasure, is my list of "My Favorite Non-Superhero Game Adventure Modules to Use for Superhero Gaming!" Huzzah!
WARNING: Possible Old School Module Spoilers. Don't say I didn't warn you.
GW1 Legion of Gold (Gamma World, TSR 1981)
After defeating a major villain of the high technology, world-conqueror/megalomaniac variety, the heroes discover the bad guy's hidden cache of failed and/or unfinished projects. Among them are a set of golden armored robots and a small sphere. Messing with the sphere sends the team into the distant future. At that point, run the module as normal with the goal of relocating the time shifting globe before a villainous future mutant does.
In a Marvel setting, perhaps the robots, sphere and other items were obtained from Kang, The Conqueror. In DC, travel to the future world of Kamandi, the Last Boy on Earth. Perhaps there is a villain controlling the gear in the future who is a descendant of the villain the PC's defeated in the first place. Maybe it is the villain himself, having survived into this distant time of apocalypse.
S3 Expedition to the Barrier Peaks (Dungeons & Dragons, TSR, 1980)
In an attempt to escape from local authorities and/or superheroes, a low grade telepath hides in the mountains near his small town. Deep in the recesses of this poorly mapped locale the psionic comes across a cave that leads to an advanced spacecraft buried for hundreds of years. While exploring the ship, the uninvited guest locates a suspended animation pod containing the vessel's only Human survivor, the ship's commanding officer. The telepath attempts to read his mind and is overwhelmed by the combination of future knowledge and latent psychic ability the captain possessed.
Weeks later the PCs are called in because the region's emergency services are overwhelmed by calls of robot monsters and all manner of strange things attacking townsfolk and travelers near the mountains. The culprit is the telepath, now believing himself to be 'Captain DarkStar' or something and getting the original crew's mission horribly garbled in his now severely deluded mind.
In Marvel, the telepath is a Mutant and the vessel is a lost Kree or Shi'ar ship. In DC the vessel could be from any number of worlds or from the future (the Legion's 30th Century or the alternate 21st Century of Tommy Tomorrow). Perhaps the persona of the telepath is fighting to break free of this gestalt mind and will aid the PCs if possible.
EX 1-2 Dungeonland and Beyond The Magic Mirror (Dungeons & Draogns, TSR, 1983)
If you are unfamiliar with these two brilliantly twisted modules for shame on you. They are two of Gary Gygax's last, great, acid trip adventures before his departure from TSR. They are also perfect for Superhero RPG players who are getting a little too full of their ability to leap tall buildings and bend steel with their bare hands. There are so many ways to go with these two devilishly, dangerous diversions into the world of Lewis Carroll's Alice in Wonderland that I hardly know where to begin.
In Marvel, perhaps none of it is real and rather an elaborate high-tech trap filled theme park built by Arcade. The same could be done in DC if the Mad Hatter teamed up with a high technology villain. However, a team-up of Mad Hatter and Mr. Mxyzptlk would pretty much kick ass too and everything would be 'real'.
I6 Ravenloft (Dungeons & Dragons, TSR, 1983)
The PCs can easily get caught up in the Count's plot, either by finding themselves in the middle of the conflict, while investigating some other crime (which may or may not be connected) or because one of them has supernatural ties.
In a Marvel game Zarovich may be an enemy of Morbius, The Living Vampire or trying to steal the mystic power of Dr. Strange, Ghost Rider or another supernatural character. In DC I could see Strahd becoming obsessed with Zatanna, which distracts him from his normal goals unless he thinks he can use her to defeat his vampire enemies. Also, the often forgotten Lord Bennett of I...Vampire could play a role in the story.
Heheheh...more ideas are on the way...