I wish I had enough experience with a large number of species, but I can really only respond according to the two I have - and the winner of the Biggest Ham award would definitely go to Jerry. He's larger than life, has no idea he is only 33 grams, and just loves life. He plays nonstop, he talks nonstop, and he flies and zips around everywhere checking out whatever we're doing. I do not know how such a tiny thing can have SO much energy!

He makes up the funniest word combinations and nicknames - he calls himself "Jerry G" currently!
Right now he's meowing as his favorite cat walks by and grasping his bell in one foot and ringing it. He's also muttering to himself "little budgie......*meow*.....that's a good birdie...."