[10.6] These sprites share the same script, how do I know which one got clicked?

In lieu of a sensible "me" keyword, Director provides the clickOn function to tell you which sprite has been clicked. Suppose you have a bunch of buttons which change colour when clicked. They could all share the same script, something like this:

on mouseUp
  put the clickOn into me
  set newColor = (the foreColor of sprite me + 1) mod 256 
  set the foreColor of sprite me = newColor end mouseUp

The first thing the script does is determine which sprite it has been called for, and then it acts on that sprite.