Customers need to sign up for Comcast’s Blast!, Extreme 50 or Extreme 105 broadband plans to qualify for the promotion, which means they will be signing up for broadband services that have at least 25 Mbps downstream. But those broadband bundles don’t come cheap — Blast starts at about $53 a month, with Extreme 105 broadband services costing an introductory$105 a month for the first 12 months. (Prices for Extreme 105 increase to $130-$150 after the first year.)