Newegg via eBay offers the Motorola Arris Surfboard 600 Series DOCSIS 3.0 Broadband Cable Modem, model no. SB6183, for $89.99 with free shipping. That's $9 under our mention from three days ago and tied as the lowest total price we've seen. (It's also a current low by $9.) It features download speeds of more than 600Mbps and upload speeds of more than 100Mbps.
Note that this modem may not be compatible with all service providers.