What cell phone carrier has the cheapest Family Plan with internet?

In large owner surveys, T-Mobile often finishes neck and neck with Verizon Wireless. Subscribers say Verizon Wireless has slightly better call quality (especially in the Northeast, Mid-Atlantic and Western states), but T-Mobile earns better scores for service plan options, billing and cost of service in nearly every region of the United States. Also, it's possible to get a T-Mobile world phone that works in the U.S. and abroad, whereas Verizon phones will only work in the U.S. T-Mobile's least-expensive plan costs $30 per month, which gets you 300 anytime minutes and unlimited weekend minutes, while the $40 plan gives you 600 anytime minutes, plus free nights and weekends -- a better value than Verizon's cell phone plans.