Cloned Cube is a Portal mod. It takes place after GLaDOS' fall in Portal. You assume the role of Chell's secret clone. You have to escape or else you may just be tested to death. There is one obstacle. CUBiS is trying to kill you.
Some old Performa Macintosh computers that Aperture has been keeping around reminiscent of their old days. Somewhat modeled on a picture of a Performa.