Any hoo, here's some of my favorite Marvel "urban legends" courtesy of the CBR weekly article I mentioned earlier (as you will see I LOVE behind the scenes fight between creators spill out into the public forum......ahhhh pre internet days!):
 1. Al Milgrom was fired by Marvel for sneaking an insult towards Bob Harras into a comic book.  
Al Milgrom apparently was not a fan of former Marvel Editor-in-Chief, Bob Harras.  Milgrom was formerly a member of Marvel editorial, but had left to be a freelancer.  In the late 90s/early 00s, Milgrom had a deal with Marvel to do freelance inking for them.
In August of 2000, Bob Harras was replaced as Editor in Chief of Marvel Comics by Joe Quesada.  A few months later, Universe X: Spidey was released, which was a  one-shot story tied into the Earth X/Universe X/Paradise X trilogy by  Jim Krueger and Alex Ross.  The story was drawn by Jackson Guice, with inks by John Stansici, Johm Romita Sr. and Al Milgrom.
At one point in the story, Al Milgrom snuck into the backround of a  panel, along the spines of books on a bookshelf, the phrase, "Harras, ha  ha, he's gone! Good riddance to bad rubbish, he was a nasty S.O.B."
		
		
	
	
2. Artist Joe Jusko dressed up as Captain America for the cover of a comic book.  In 1982, he posed wearing a Captain America costume on the cover of Marvel Team-Up #128, a book I own.
3. Roger Stern left Avengers over Captain Marvel's leadership of the team.
 
In 1982, Roger Stern introduced a new Marvel superhero, who he gave the (then available) name of Captain Marvel.  This young heroine joined the Avengers as a member-in-training, and  soon rose in the ranks until the point, in 1987, that she became the  leader of the Avengers. Which was a notable feat for one of the first  significant black female superhero.
 
This was all fine and good, but in 1988, Avengers editor, Mark  Gruenwald, had different ideas about the character. He wanted Captain  America to become the leader of the team (conspiracy theories abound  that since Gruenwald was the writer of Captain America's book, that he  wanted Cap to lead the Avengers to aid in publicizing Captain America's  title...which I do not think is fair to Gruenwald. It is just as likely  that he just decided that it was better for the book for it to go down  like this).
 However, Gruenwald did not just want to have Captain America become  the leader, he also wanted Captain Marvel to be shown as an inferior  leader before she was taken off the team (presumably to further show how  adept Captain America is at the role).
Stern, creator of the character, reasonably balked at this change, as  he felt such a move would be hard to do without looking racist or  sexist, and therefore, Stern, who had been writing the title for the  past 60 issues or so, was taken off the book, and replaced by Ralph  Macchio and then Walt Simonson, who both basically followed Gruenwald's  prescribed plot path (until Simonson then took the book in his own  direction).  Which is a shame, as the decision really took Captain Marvel, who at  the time had become as mainstream as you could get, off the road of  "mainstream" basically for good.
4. Kevin Smith killed off Mysterio without permission from the Spider-Man editorial office.
In 1998, Kevin Smtih began his acclaimed run on Daredevil, with Joe  Quesada on art, which helped launch the Marvel Knights line of comics  (Marvel Knights was actually a separate branch of Marvel, with a  separate editor in chief and everything! It was made up of the  infrastructure of Joe Quesada's own company, Event Comics). The main  plot of Smith's storyline was that an old Spider-Man villain, Mysterio,  was dying, and decided to go out in a bang by thoroughly destroying his  arch-nemesis, Spider-Man. However, at the time, Spider-Man was currently  a different character (Ben Reilly), so Mysterio decided to adapt his  plan to someone else, namely Daredevil.  At the end of the story, Mysterio kills himself.
The problem, continuity-wise, came when a month later, Mysterio  appeared in the pages of Amazing Spider-Man...fighting Spider-Man!!
 It all came down to the fact that, when Spider-Man editor Ralph  Macchio was asked if they could use Mysterio, no one mentioned that they  were going to kill him off! The Spider-Man editor already had plans to  use Mysterio in the pages of Amazing Spider-Man a few months after the  Daredevil story was to finish.
As you may recall, Daredevil ran a bit late, so the conclusion of the  arc ended up coming out AFTER the Amazing Spider-Man arc had begun, so  while Mysterio was dying in one comic, he was the big villain in  another.
 Smith later claimed that no one told him that he specifically COULDN'T kill Mysterio.
5. Kurt Busiek came up with the idea for Jean Grey's 
original return from the dead!
Shortly before the publication of Uncanny 
X-Men
  #137, future freelance writer Kurt Busiek, then still a college  student, heard about the upcoming events through the fan grapevine, as  did fellow future comics pros Carol Kalish (who would go on to head up  Marvel's Direct Sales Department for years) and Richard Howell (artist  of the Vision and The Scarlet Witch 12-issue maxi-series, among others).  The three of them also heard that Jim Shooter had declared that Jean  Grey could not be revived unless it was done in such a way as to render  her guiltless of Dark Phoenix's crimes. Taking this as a creative  challenge, all three then-fans decided to come up with their own  resurrection scenario. Busiek's involved the discovery that Jean Grey  was still on the bottom of Jamaica Bay in suspended animation, and the  Phoenix entity had used her body and mind as a lens, creating an  immensely powerful duplicate of Jean, but a duplicate which grew more  corrupted and distorted the longer it remained separate from the true  Jean.
in 1983, after beginning a career as a freelance writer  the previous year, Kurt Busiek attended a comics convention in Ithaca,  New York, staying at the home of Marvel writer Roger Stern. In  conversation, both writers' longtime interest in the X-Men came up, and  Stern expressed regret that there was no way to bring Jean back, not  while satisfying Shooter's edict. Busiek told Stern his idea, not  expecting it to amount to more than idle conversation. Later, Stern told  the idea to John Byrne, then writer/artist of Fantastic Four.
In 1985, Jim Shooter greenlighted a new series that would reunite the  original X-Men into a new team called "X-Factor," to be written by  longtime freelancer Bob Layton. Hearing of this, Byrne called Layton and  suggested Busiek's idea as a means of raising Jean Grey from the dead  while satisfying Jim Shooter's demands for total absolution for Jean.
