What do you know,
Wolverine was indeed in that Transformers/Avengers crossover...
I'll edit the above and it is indeed "Six Degrees Of Separation"!
And TerraEsperZ, that whole TV multiverse thing is insane! o_0 Awesome find! Though I'm guessing some links are iffy, it's certainly easier when many shows take place in the present day, and it's not hard, especially within the same network, for an actor, in character, to make some cameos on other shows.
I like the crossovers in comics where somewhat epic stuff actually happens (ironically I haven't read any of them other than the summaries on Wikipedia, but the ideas are appealing), though the video game mash-ups and cameos where the meeting isn't fully or well-explained (DreamMix TV World Fighters, the guests in Soul Calibur, Marvel Vs. Capcom, Mortal Kombat Vs. DC Universe (I'm guessing), etc.) are still interesting enough, and often key to linking the more disparate properties together.
I mean, extending from the above, the Marvel Comics characters have met the DC Comics characters, Batman has met a Predator (I'm not counting that Internet fan film a few years back, but rather the comic
Batman Versus Predator), and the Predators (if we can extend it to the whole race or whatever) have met Aliens. Who would've guessed that Aliens and Bomberman are in the same realm of fiction? o_0 I remember Lara Croft has fought Aliens too...
And yes, I do remember the Cartoon All-Stars To The Rescue. Weren't the Teenage Mutant Ninja Turtles in there? And Garfield? If I'm remembering correctly, that could do a lot. Surely some comics characters must have met the TMNT... (I know The Punisher met Archie, maybe Archie met the TMNT at some point? That's a guess.) And maybe we can go from Garfield to some of the other daily newspaper comics, there must've been a crossover at some point, like in the April Fool's Day ones...
I actually don't read comic books at all, it's rather suprising how much I know about them just from a few key cartoons and Wikipedia.
And a memory that likes to latch onto anything remotely quirky...I never would've known about Batman Versus Predator if not for a random poster at a video game rental place this one time. That was all it took for me to file it in my geeky memory.