College Humor has a great post titled “New Punctuation Marks for Grammar Nerds”.
It includes things like the Double-Reverse-Sarcasticmark, used to denote either sincerity or sarcasm, depending on the sensitivity of the reader; and Isolation Marks, used to quarantine bad spelling, so it’s clear who owns the shame of the mistake.
My favourite, however, is the Demicolon (pictured left).
The Demicolon can be used to connect anything to anything else, grammatical or otherwise – even a picture of a bear and the planet Neptune. Awesome.
Victory-Captures-The-Wind is a close second.
Read the full list, with examples, at College Humor. ((Shall I quibble over the incorrect spelling of “humor”, or let it slide because they’re American?)) We need to implement this.
Ph’nglui mglw’nafh Cthulhu R’lyeh wgah’nagl fhtagn. ((Also, I love this example.))