In Kingdom Hearts, I can shatter rocks with Sora's feet.
? Can you tell me how that works?
As for me... favorite glitch, or one I've gotten the most utility out of, is probably from Ratchet & Clank: Going Commando
, where entering first-person mode and throwing the wrench in the middle of double-jumping can let you climb walls infinitely. Good for sequence breaking and makes certain Platinum Bolts easier to reach, but I think you have to have beaten the game at least once to unlock FPS mode anyway...
Next up, would be the Mine glitch in Fire Emblem