Creep capping is the practice of secretly screen capping someone on video chat without their knowledge. It's commonly used on video chat sites such as omegle and chat roulette. Caps are later uploaded onto social networking sites or kept in picture folders to look back on.
Roza: "OMG. He's hot. Did you creep-cap him?"
Taylor: "Yep! He was so gully. He had no clue!"