Super Street Fighter IV: Arcade Edition - unlock Special Movement - £0.10
This one's pretty easy, you just have to use a special move 100 times. Start up a local Versus game against a CPU, and pick E Honda, Chun Li or Blanka as your character.
Pick the CPU as any character you want, on the lowest difficulty setting, make time infinity and 7 rounds.
E. Honda and Blanka have a special move they do by mashing the punch button (Chun Li's is by mashing the kick button). Just keep doing that special move until the achievement pops. If you don't get it by the time you finish the match, just click Rematch and keep doing.
You can tell the special move was used by Honda attacking with a million hands, Chun Li attacking with a million feet and Blanka using electricity.
This cannot be unlocked in Training Mode. Not sure if it can be unlocked in Challenge/Trial mode, wasn't willing to risk it.