The Interrobang

From Wikipedia:

The interrobang is a rarely used, nonstandard English-language punctuation mark intended to combine the functions of a question mark and an exclamation mark. The typographical character resembles those marks superimposed one over the other, and the name interrobang comes from interro – from interrogative – and bang – used to amplify the exclamation. In informal writing, the same effect is achieved by placing the exclamation point after or before the question mark; e.g., “How could you do such a thing?!”

American Martin K. Speckter concocted the interrobang in 1962. As the head of an advertising agency, Speckter believed that advertisements would look better if advertising copywriters conveyed surprised queries using a single mark. He proposed the concept of a single punctuation mark in an article in the magazine TYPEtalks. Speckter solicited possible names for the new character from readers. Contenders included rhet, exclarotive, and exclamaquest, but he settled on interrobang. He chose the name to reference the punctuation marks that inspired it.