There is a special offer for this great game here:
http://www.microsoft.com/games/en-gb/community/Pages/dealoftheweek.aspx
Reviews from Metacritic are here
http://www.metacritic.com/game/pc/osmos
http://www.microsoft.com/games/en-gb/community/Pages/dealoftheweek.aspx
Reviews from Metacritic are here
http://www.metacritic.com/game/pc/osmos