Right now, Woot is selling the ARRIS/Motorola SURFboard SB6183 for $49.99. This is perhaps not as good as the previous deal on this site, but this is for a new modem with a 2-year warranty and not a refurbished one like previous deals I’ve seen here. They do have a shipping charge of $5 that covers your whole order.
I’ve been using this modem for about a month now and it works great. Hope this helps.