Hey, It's That Guy!: we have Matt Hooper, who survived his earlier brush with a great white shark but here gets mauled by piranha in the first 5 minutes of the movie. Meanwhile, the guy from TV's Sliders gets his penis bitten off by the title monsters.
What Could Have Been: The Bluray of Piranha 3D reveals two abandoned sequences storyboarded that are even more over the top than some of the Piranha attack sequences in the movie. One of the sequences was filmed for the sequel.