ForeverGolf
This language extension makes every operation loop, and was created by User:Poolala. The reason this was made was to create some interesting code golf programs.
How it works
To show how it works, I'm gonna take the language Brainfuck, and put the ForeverGolf extension on it. Now, every operation requires an extra parameter: how many cycles until it executes again.
If an operation hasn't executed yet, it waits its number of cycles before it executes.
If two operations are set to run at the same time, the operation that's closer to the beginning of the file goes first.
For example, +:1 -:3
would do this in normal brainfuck code: nop + + + - + + + - + + + -
in an infinite loop.
Note: only add the extension to true operations, not labels, function declarations, etc.