keyboard buttons assigned to icons

Hi guys, I was wondering if there was anyway to create a new shortcut icon on an objectdock but have that icon represent a keyboard key

I'm basically looking at buying a new windows8 tablet and wanted a dock on the left hand side for Ctrl, Alt, Shift and Spacebar

So when the icon in the objectdock is continually pressed down it would be like pressing down on the one of the above keyboard keys

 

Does anyone know of a way of doing this?

 

Thanks