I just got the verizon mobile fivespot wtih 3gb of internet usage a month. The guy at bestbuy said it was about 150 hours of internet a month but some people go over. What does this mean? Will I go over if I, say, stream movies from netflix? Is it how many cookies you use off the internet? How much does opening a page or sending an IM use? I dont understand how much 3 gb is, can anyone help?