Thus everything from Conan to the Kroot are in my campaign world (though the timeline covers approximately 4 billion years BC to 40,000 AD if you can guess why. 22 years of gaming has really built up the old binder collection (8 of them now).
Sadly, because I despise RetCons (especially in-game) A LOT of the initial things - especially for the supers, was crafted when I was 13, and so some of it is tool-ish. All apologies to DC, Marvel, Image, etc.
Besides there are LOT of differences between the sources and the kit-bash I've got going on...at this point, most of the commonality is simply names.
Such as:
SkyNet is actually a temporal computing device with links to the Borg and an Avatar of Nyarlathotep (as are the Borg)
StarFleet is the continuation of the ROBOTECH timeline linked with Babylon 5...the RDF becomes GroundCorps
Haydon V is the Eternal Emperor and Earth is but a lost colony, isolated during the Warp Storm birth pangs of Slaanesh
The Power Puff Girls grew up and became The Mange, Harmony Bunny and Liberty Bell and Adam Magnum, MD, PhD, Wizard (the Third most intelligent man in the world, after Reed Richards and Victor Von Doom...Dr. Emile Lang is #4)
Bunny (the fourth PPG) ran away and was raised by Doom, along with Valeria (from FF4)
Hogwarts is a Chantry for the Traditions on a Horizon Realm
The Technocracy has the public face of the UN Rapid Deployment Force (yes...from ROBOTECH), Section 6's intervention force is Mithril who masquerades as mercenaries and the Tetragrammaton Clerics...
The Green Lantern Corps was founded by Oans (the third of the Old Races along with Shadow and Vorlons) and acts as a counterpoint to the Imperium's Inquisition...
etc. etc. etc.