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Jefailey of Divekick (pictured above) has this as his character gimmick: Due to his ego, his head inflates every time he wins a round. This makes it easier for opponents to score headshots on him during later rounds. However, the larger his head gets, the higher he jumps (since it's full of hot air), changing his kick angle.
In Toon Town Online, one of the rewards for completing a "Just for Fun" Task is your Toon to receive a giant head for a varying period of time, depending on which Playground tasks you're working on.
Soun Tendo from Ranma ½ tends to do this when upset (usually when finding yet another long lost fiancée or the like that Ranma has been promised to marry), sometimes with demonic assets like a snake's tongue or tentacles.
A common feature in Naruto fanfiction is the "Big-Head no jutsu", used by teachers (ie: Iruka Umino and the Sandaime) to quell unruly students in class.