Supervisor: Christian Cherek Thesis Topic: Solving reachability issues on a big multitouch tabletop

I am currently working on my Master Thesis at the Media Computing Group, supervised by Christian Cherek, where I have to solve reachability issues on a big multitouch tabletop. For example, the prototype I will use is about 1.5 x 2.5 meters big, so how does someone reach a virtual or maybe even a physical object that is located far away on the screen.