Rollen Stewart, better known as "Rainbow Man", made a flaky career out of appearing at sporting events with a rainbow clown wig, holding up signs with Bible quotes and generally making a pest of himself by mugging for the camera every time it passed his way. In the '70s and '80s he got quite famous, even up to getting his own Budweiser beer commercial (for a guy doing Bible quotes?) and Christopher Walken playing him in a sketch on Saturday Night Live.
But people bitten by sudden nostalgia for the lovable loony will be disappointed in his later adventures. Stewart showed increasingly unstable behavior, having been married four times and committed at least one reported act of domestic violence. But then, as told by The Straight Dope:
"He set off a string of bombs in a church, a Christian bookstore, a newspaper office, and several other locations. Meanwhile he sent out apocalyptic letters that included a hit list of preachers, signing the letters 'the Antichrist.'"
" On September 22, 1992, believing the Rapture was only six days away and having prepared himself by watching TV for 18 hours a day, Stewart began his last "presentation." Posing as a contractor, he picked up two day laborers in downtown LA, then drove to an airport hotel. Taking the men up to a room, he unexpectedly walked in on a chambermaid. In the confusion that followed he drew a gun, the two men escaped, and the maid locked herself in the bathroom. The police surrounded the joint, and Rollen demanded a three-hour press conference, hoping to make his last national splash. He didn't get it. After a nine-hour siege the cops threw in a concussion grenade, kicked down the door, and dragged him away."
The upshot of that is he is currently serving three consecutive life sentences. He was also the subject of a 1997 documentary Rainbow Man, directed by Sam Greene. A clip:
...and there goes another tragic monkey devoured by the media.