I think I've found two shiny Pokemon. A shiny Oddish in Fire Red or Leaf Green, and one other shiny of equally low-tier Pokemon, so nothing too exciting.
However, my brother, that JACK***, legitimately caught a shiny Kyogre in Sapphire without even trying. Somehow, he just walked up to it and it was shiny, despite there being people out there who will reset the game over 2,000 times for a legitimate shiny Legendary.
That's not why he's a jack*** though. He's a jackass because some time later, when he wanted to replay the game, he DELETED THE SAVE FILE WITHOUT TRADING THE KYOGRE. Everyone in my family gives him crap about it any opportunity we can.
EDIT: Whoops, looks like that particular compound word expletive isn't covered by the censors. Allow me to do some TV-style censoring don't ban me pls