Walmart offers the factory-refurbished Motorola Surfboard DOCSIS 3.0 Cable Modem, model no. SB6121, for $26.97. Opt for in-store pickup to dodge the $5.97 shipping charge. That's tied with our mention from a week ago and $3 under the lowest price we could find for a refurb. It features support for IPv4 and IPv6 and enhanced network management. A 90-day Motorola warranty applies.