I just found out the Kool-Aid Man is 35 years old this year. From Wikipedia:
In 1975 Kraft Foods created the character’s first costume with arms and legs. He also became more of an action figure in commercials — performing extreme sports and busting through brick walls. Kool-Aid Man is famously known for shouting, “Oh, Yeah!” as he is summoned by thirsty children with the phrase, "Hey, Kool-Aid!". Commercials of the era also featured a catchy jingle, always ending with the Kool-Aid Man's phrase.
Here's a typical Kool-Aid Man ad from when I was a kid.
And, here's the now legendary Kool-Aid Man appearance on Family Guy.
Happy Birthday, Kool-Aid Man!