The game is based on this
one, called "Narbacular Drop". Playing this is basically playing portal without the fancy graphics
You can download Narbacular drop for free. It was made by a bunch of students, and as soon as valve saw it, they hired the entire production team. VERY cool stuff.
Hope you guys have as much fun playing it as I did
P.S. If their site is down, Here are their external download links.
http://www.vgpro.com/file/10873_narb..._drop.exe.html
http://public.planetmirror.com/pub/v...cular_drop.exe
http://www.fileplanet.com/161458/160...5BFree-Game%5D
http://www.digipen.edu/GameGallery/d...acularDrop.exe
http://www.filecloud.com/files/file.php?file_id=3611
(Filecloud is by far the easiest to download from.)