AC POWERLINE NETWORKS for this one.
Try http://www.netgear.com/Products/PowerlineNetworking/PowerlineWirelessAccessPoints/WGXB102.aspx and shop around for price or similar solutions.
i own a ps3 and it is connected to a Wireless-N Broadband Router WRT300N. My wireless router is two floors above my ps3. The only problem with this is that it loses connection sometimes because the wireless signal strength isnt that good and the connection is not as fast as if i were to put the ps3 up one floor in my living room. Would a wifi repeater solve this problem? I can't use a long ethernet cable to make a wired connection for my ps3 because my parents don't like it.