goodnight, sweet prince

the original line is "goodnight, sweet prince/and flights of angels sing thee to thy rest" spoken by Horatio in Shakespeare's Hamlet

What the internet writes on pictures of celebrities along with
(celebrity DOB) - (current year) when it's trying to convince you they died recently. This has evolved beyond an actual trick into a treasured meme.

A phrase mostly used on internet forums such as 4chan when a major celebrety (usually a black male) "dies". This is not usually the case, and usually it is used to trick people into thinking that said person has died. (A corresponding picture will most likely accompany a non-matching name.)
The phrase takes its origin from The Big Lebowski, a 1998 movie starring Jeff Bridges and John Goodman, whose character (Walter) utters the phrase as Steve Buscemi's character's (Donny) ashes are spread into the ocean.

when you knock out someone who is very snobby, or a person dell deserved of that knock out.