I've encountered a few other shiny Pokemon in most of the games. I saw a shiny Pidgey in Silver, although I don't know if I caught it, and a shiny Machoke in Crystal, which I know I didn't catch because I accidentally caused it to faint. I don't think I saw any shiny Pokemon in the third generation games, but I could be mistaken. I got a shiny Bidoof in Diamond and a shiny Roggenrolla in White. I got Pokerus in Ruby, but I had no idea what it was and I thought that it meant that there was a problem with my Pokemon. I got it again in Pearl and then in Platinum, the latter most likely being the result of trading an Elekid with myself. I didn't get the Pokerus in either Black or White though.