It used to be that websites and their interactions were much different than those from native software applications. Well this is not so much the case anymore. Mary Lou, a freelance web designer and developer from tympanus.net, wrote an interesting article discussing a few different morphing buttons concepts that showcase some amazing possibilities for web interactions.
She has created a handful of really nice interaction effects that occur when buttons are clicked. They appear as if content or elements are contained from within them and when clicked they transition out from within the button in many different ways.
They are great effects but you will want to keep in mind that they only work in more modern browsers.
You can read the full article here