Revenge is a dish best served cold. And so as the four major carriers look to serve up the iPhone 5 as a treat to those who’ve been patiently waiting for its release date, they’re each preparing to take out the legs of their own customer base in their own special way. There’s Verizon, who’s prepared to tell you how often you can use your iPhone for basic tasks. Rival AT&T wants to do the same, but it’ll put your life into slow motion instead of charging you extra. T-Mobile is busy pulling off the double-dish stunner of folding itself into the kind of carrier most of its customers were specifically trying to avoid while still... leaving them in iPhone limbo. And Sprint, well, there’s no telling what the nation’s soon to be smallest...