I bought GalCiv2 complete, Sins of a Solar Empire and entrenchment.

I installed the games in the fixed PC I use at home;

it is a desktop with an intel 3GHz CPU, 1GB memory and a Geforce 6800.

Now, since I am frequently away from home , I would like to play the games ALSO on my notebook:

it is a T5850 core 2 machine, with 2G memory.

The problem is : I would like to play the game alternatively on BOTH the machines. So, I would like to install the games in the notebook without disinstalling them on the desktop.

How can I do?

Thank you.