The super wavedash is a physics exploit in Super Smash Bros. Melee that can only be performed by Samus. If done correctly, Samus will travel approximately the distance of Final Destination. However, it is important to release the control stick after the player performs the move, otherwise the distance will not be as far.
In order to do this, drop a bomb, and as Samus is hitting the ground, immediately hit the opposite direction desired approximately when Samus lands after dropping the bomb, then hit the direction desired. This will result in Samus sliding across the level, as if in a normal wavedash, but she will go much farther.
It is possible to do a super wavedash falling from the air, but a bit more difficult since the player does not have the ground to judge the timing as he or she may fall though the air from different heights. It is also possible to cancel it in order to avoid a self-destruct. Doing any move with the exception of jumping, sidestepping, using the Charge Shot or smash attacks will stop the super wavedash.