What is the cheapest way to get and Edge-only data plan for an unlocked iPhone 3G on T-mobile in the U.S. with T-mobiles current data offerings? I had read that the T-zones plan was the way to go, but it looks like T-mobile has revised their data offering and I don't see it online. It looks like I have the choice of adding unlimited data to the current plan for $30 or switch to a package plan that includes data, but fewer voice minutes for $20 over the current plan. I believe both of those plans include 3G, which won't work on the iPhone 3G on T-mobile. So is there another option that is Edge only that isn't on their website? Thanks.