Portal is one of the most famous and elusive games in video game history; I knew about it but never actually played it until recently. After playing I can say it blew my expectations away and may be one of the coolest games I've ever played. The puzzles are great and the eerie atmosphere works wonderfully. The game's biggest advantages are the portal concept which is genius and GLaDOS who is both funny and unnerving. This is a great game if you can get your hands on it.