Amazon offers Prime members the Linksys Advanced DOCSIS 3.0 Cable Modem, model no. DPC3008-CC, for $24.99 with free shipping. (Non-members can spend $35 to qualify for free shipping; otherwise, shipping costs $8.74.) That's the lowest total price we could find by $18, although we saw it for $5 less in November. It supports download speeds of up to 340Mbps. It's certified for use with Comcast Xfinity services; check with your provider if you use a different service.