Sort everything with Polymorphism by (VB2TheMax, Francesco Balena)

Now this is a bit of fun. You can use CallWindowProc to call any function provided it has the same arguments as a WindowProc function (four long parameters and one return long). That means that any function you can call AddressOf on in VB that meets this template can be used as a callback. The article describes this technique and demonstrates using it to create a polymorphic Shell Sort.