Everyone I know loves Portal. I do not know a single person that has played Portal that he/she was not really enthusiastic about it, and there is no denying that the Portal Gun is really cool. A Graphic Designer from Atlanta US has build his very own real size Portal Gun. Of course, it doesn't open portals, but it looks really cool with blinking orange and blue lights and everything. Go check his blog to see how he managed it.
Oh, by the way, listen to Portal's finale song which is possibly the best finale song in the history of video games.
And remember, 'the cake is lie....'