today is the second day of the Negg event. I don't think there is a trophy... just item-prizes, an annual avatar and maybe a site-theme? I can't remember very well actually. you can catch up from previous days though!
I used to love it before Nickelodeon took over and turned it into a cash cow.
I remember that before you could transfer pets, people would make deals and say "I'll disown this pet at this hour" and someone else would snatch it.