This is essentially a three pack of Windows 7 home which includes Windows Media Center. Its one disc with three keys so it can be installed on 3 PCs. Amazon has it on sale for $109
http://www.amazon.com/dp/B002MV2MG0/m=ATVPDKIKX0DER
http://www.amazon.com/dp/B002MV2MG0/m=ATVPDKIKX0DER