The laser-rainbow gunfight towards the end of the "Blow" video. Ke$ha and James Van Der Beek walk away from each other after the conversation mentioned below as the song plays quietly in the background. Suddenly, Ke$ha screams "THIS PLACE ABOUT TO-!" and epicness ensues.
The "We R Who We R" video has Ke$ha flinging herself off a twenty-story building and being caught by the partyers below, unscathed. To quote a commenter on Youtube, "those hands defy the laws of physics."