Newegg offers the Linksys Powerline HomePlug Adapter Kit, model no. PLEK500, for $89.99. Coupon code "EMCWHHG42" cuts it to $69.99. With free shipping, that's $8 under our January mention and the best price we've seen. (It's also a current low by $18.) These adapters plug into a wall power outlet to expand your home network without having to run Ethernet cables through your house and support up to 500Mbps data transfer rate.
Update: Specs corrected.