Watchtower Database (if you like the DCAU you should subscribe)
gives the equivalent of the Westphall Multiverse for the DCAU. Basically the DCAU touches all other versions of DC properties, the Scooby Doo multiverse (this also means that the whole Hannah Barbera multiverse is also linked in, but he doesn't mention that), the TMNT multiverse, Archie, the Green Hornet, the Bionic Woman, the (British) Avengers, the Looney Tunes/Freakazoid/Animaniacs multiverse, etc.
The phrase "turtles all the way down" comes to mind. This stuff will drive you insane if you let it.
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mudshark: Nate's just being...Nate.
Zeke: It comes
nateurally to him.
mudshark: I don't expect Nate to make sense, really -- it's just a bad idea.
Sa'ar Chasm on the 5M.net forum: Sit back, relax, and revel in the insanity.
Adam Savage: I reject your reality and substitute my own!
Hanlon's Razor: Never attribute to malice that which can be adequately explained by stupidity.
Crow T. Robot: Oh, stop pretending there's a plot. Don't cheapen yourself further.