Mario Tornado
The Mario Tornado is the name given to Mario's Down B in the first two installments of the Super Smash Bros. series. The move involves him rotating rapidly with his fists outstretched. The Mario Tornado can be used for recovery as well by rapidly tapping B, which allows you to rise in the air slightly. It is a multi-hit attack, and can spike in the original SSB64.
In Super Smash Bros. Brawl
In Super Smash Bros. Brawl, Mario's Down B has been replaced with F.L.U.D.D.. In the DOJO!! update revealing this change, a screenshot of the Mario Tornado is shown with the accompanying caption: "He still seems to have this move, though. Eh? Is it a normal attack?!" The E For All demo revealed that the Mario Tornado is now, in fact, Mario's down aerial move. The move is much quicker now, although it is weaker and can no longer help Mario's recovery.