Urban Dictionary

Intentionally posing in other people's photos, for a later surprise.
Usually people making funny faces in the background, without the knowledge of the main subjects of the photo.

Used in many MMORPG's to indicate that you will be away to go to the restroom.

How the fuck.

Charity Mugger. One of those people who stands in the street with a big brightly-coloured bib and quite possibly a clipboard soliticing donations to the Feline Liberation Army or some other worthy cause.

To become enraged; to lose one's temper, clothing and power of coherent speech before embarking on a spree of violence and wanton destruction. After the comicbook character who turned from an unregarded geek into a thundering green mass of unstoppable fury.

Vomit or snot from a baby found around the upper chest or shoulders of their father which shows the world that they are a parent.

Personification given to mainly booze, and sometimes referring to other drugs. Generally used to refer to drugs when a person is feeling down and a person is saying it's what they need and/or use to feel better.