I tried to make this as compact as possible, if you have any suggestion please let me know, Also it was brought to my attention that CNB has a similar design I have went and checked it out, But mine's more compact and there are several differences.

To win the steam copy of portal 2, You do not need to subscribe nor like.. That's your choice. The information is in the description and in the video.

http://www.youtube.com/watch?v=cETyDlK7dYY&context=C3623474ADOEgsToPDskLBXggK8cWYJoPYn06n_nan