In the eighties and nineties the X-Men became the hottest thing in comic books, thanks not only to Wolverine but to some characters created by Dave Cockrum including Nightcrawler and Storm.  The team could have been much different though.  While Cockrum was working at DC Comics, he submitted several characters for their team the Outsiders.  Not all the characters were accepted.  Later after he had gone to Marvel, he was given the go ahead to use Nightcrawler, one of the rejected characters.  Storm was a little more complicated, being a combination of four rejected Outsiders characters.