Big-Cat
Challenge accepted.
It's spelled Shinkuu Hadouken (really minor I know), but you did have the name right.Also, only Zero Laser is similar to the Shinku Hadoken.(I may be off on the spelling or name, I have no way to play Street Fighter IV at the moment)
The majority of the Final Smashes were at least based on something of the character or their games. Link's was very likely based on a mix of Cloud's Omnislash and Link's finishing move in OoT. Samus' was based likely on both the Shinkuu Hadouken and the Phazon Beam from Prime. Zamus' was probably based off of Super Metroid's Crystal Flash.
@Ove
Metsu Hadouken is Ryu's Ultra. Shinkuu is his super.