Which sci-fi character made frequent cross-show cameo appearances on non-sci-fi television?

Answer: The Observer

Although it is not uncommon for a science fiction character to perform in another science fiction television series, it is almost entirely unknown that sci-fi characters appear non-existent. Science fiction television programs. That is, unless the character is The Observer from the Fox science fiction series Fringe . As part of a subtle but far-reaching publicity for the popular sci-fi series, in 2009 Fox included The Observer ̵

1; a mysterious and easily recognizable character from the series – in dozens of situations in their networks to link the action to the show our own timeline / reality. The Observer was seen in the audience of American Idol in a NASCAR Sprint Cup race and saw, among other things, the Major League Baseball 2009 All-Star Game.

Courtesy of 20th Century Fox.