My (newly discovered) favorite trick is using the comma operator. Using it, you can (admittedly horribly) log anything in the middle of any expression.

This for example will call `console.log(myVar)` and still call `someFunction(myVar, someOtherArgument)`.

  myVar = "12345"
  someFunction((console.log(myVar), myVar), someOtherArgument);

Pretty handy sometimes :)