You can give Goku a Viking helmet in Dragon Ball Kai: Ultimate Butouden. The upcoming Nintendo DS game has a customization system where you can equip hats and wear rare costumes like a Great Saiyaman outfit. Once you make Viking Goku you can use him in an original story made for just Dragon Ball Kai: Ultimate Butouden.
This trailer has a bit more about the game’s battle system too. You can see dual screen special attacks and a dot connecting mini-game used during special attack duels.
Dragon Ball Kai: Ultimate Butouden and its funny hats hits stores on February 3 in Japan. The game has not been announced for North America, but it is a Dragon Ball game so chances are it’s coming.