Image Credit: Microsoft
mad lib n. a phrasal template word game where one player prompts others to substitute for blanks in a story, before reading the — often comical or nonsensical — story aloud [1953]*
Mad Libs is a very (adjective) game that lets (noun, plural) create (adjective) stories together. They can cover a/an (adjective) range of topics such as Letters Parents Hope Get Lost in the Mail, Instructions For the Babysitter, and even The Brady Bunch. This commercial holiday season, gather your (adjective) friends and come up with a (quantity) of nouns, adjectives, and body parts to complete the following online mad lib: ‘Twas the Night Before Christmas.
http://www.rinkworks.com/crazytales/c/c11.shtml
* being “that guy,” despite what the signs in the library say, and citing Wikipedia