Timmy was the professor's assistant on one of the itchy and scratchy type spots on the early 90's show the Dinosaurs. His role was very similar to that of Beaker on The Muppet Show. The professor would set up Timmy with a dangerous experiment, and then Step Behind The Lead Shield.

"Timmy, why don't you pour this nitroglycerine into that blender and turn it on, while I step behind the lead shield."

BOOM

"We're gonna need another Timmy!".

Classic.