One of the least restrictive activities that you may find on this wiki and the one that may spawn new games during playing.
Preparation
Consider having a book at hand might. You may also need pen and paper to write suggestions.
Setup
Choose a game leader who will run current take at the game (by volunteering or randomization).
Gameplay instructions
Main player's task is to invent a piece with a given title. Title can be provided by the audience (more fun, improvisational theatre style) or selected from a randomly opened book (usually less silly) or otherwise. The leader chooses players and instruments for the performance of his/her tune.
Game End
How to end the piece is the most important part for the main player to define. Without that in mind results of this game tend to be quite long and often monotonous (unintendedly).
Gamemaster's notes
Untied activity. Repeatable — you can have whole meetings dedicated to playing only this one game. At regular meetings with different games it's a good idea to provide a person with a title just before taking a break and later play the results of his/her efforts as a first piece after the break.
Sometimes pieces themselves take a form of a game and the idea might be worth further development — remember to write in the forums then.
Variants
At Lub/Lab jams ("Dźwięki w Lub/Labie", Warsaw, Poland) there was an additional game element: Every person wrote a proposed title on a card when entering a venue and put it in a jar. Title was to be connected to the main general theme of that day's meeting. Leader was given a random card, and the agreement was that every attendee might be asked to participate in the performance. After the invented piece was played, people that didn't play were trying to guess the title.
Example
"Puberty" from the meeting under the theme "Turning point".
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