Latios/Latias and Eon ticket
Just before you defeat the elite 4 and you hear on TV about Latios and Latias, Mix records with Ruby/Sapphire 2 times and Trade 2 pokemon (doesn't matter what pokemon, just any.) After you've done that, defeat the elite 4 and instead of the TV saying just 2 blue & red objects have been spotted, it will also say something shiny was being carried along with it and that will be the Eon ticket oh and uh, one more thing, it might (this is if you are the luckiest person to play Pokemon emerald version) rarely be the Eon ticket, the Aroura ticket and the Inferno ticket so now I have nothing else to say except happy cheating!!