Tiger Direct offers the Actiontec Ethernet Over Coax Adapter Kit, model no. ECB2500CK01, for $79.99 with free shipping. That's tied with our expired mention from five days ago as the lowest total price we've seen. (It's a current low by $15.) It includes two adapters and uses existing coaxial cables to extend a home network connection.
Dealfisher via eBay offers the factory-refurbished Netgear N600 802.11n Wireless Dual Band Range Extender, model no. WN2500RP, for $24.99 with free shipping. That's $28 under our mention of a refurb from a week ago and the lowest total price we've seen. (It's currently $43 under buying a new unit.) It features 2.4 and 5GHz bands and four Ethernet ports. A 90-day Netgear warranty applies.