Woot via Amazon offers the refurbished Arris Surfboard DOCSIS 3.0 Modem / AC Router, model no. SBG6782AC, for $74.99 with free shipping. That's $5 under last month's refurb mention and the lowest total price we've seen. (It's $54 under the best price we could find for a refurb today.) The modem supports IPv4 and IPv6 and features enhanced network management.

A 90-day warranty applies, but it's unclear who backs it.