Looking for a virtual onscreen button program

Does anyone know of a program that creates virtual buttons which can be user bound to os calls? Specifically I'm looking for a single button that I can bind, so that when it's pressed a tap will register as a right click rather than left. It must work over fullscreen directx apps (games).

Frankly the fact that MS didn't just put in their draconian design specs that all manufacturers must include a button or are on the body of the tablet to do this baffles me. Tap and Hold to right click, are you serious? On top of that it doesn't even work in most things.

This is one of the downsides of windows tablets. I might think that MS wants their users to use a mouse. This is also one of my reasons for buying a dell tablet since they have a stylus with right click and they're cheap compared to the surface.