You can now own an arcade stick for your Wii U, helpfully labeled with the one game you'd need an arcade stick for, Tekken Tag Tournament 2. The Tekken Tag Tournament 2 Fightstick S from Mad Catz is now available for $160. The controller connects to the Wiimote via a 3.3 foot-long controller cable.
PS3 and Xbox sticks are also available, called the "FightStick S+" because of extra foam padding on the bottom and swappable Tekken artwork. They retail for the same price.