Really quick tutorial.
► "this" is a global variable
► Whenever I call a method, "this" gets set to that method's current location.
► It's important to remember that "this" isn't a property unique to any object or context at compile time - when you use it in code it is always a reference to the global variable set at run time (when you call the method).
Call and Apply
► Allow us to assign what "this" is for the duration of a method call.
Cats and dogs living together
What else can we do with it?
Why won't JS let me push array elements onto numbers?
Anything mildly legitimate we could do with it?
Inheritance the correct way (as stolen from John Ressig)
Check it out, multiple inheritance!