We always thought one of the big draws of prepaid plans was simplicity, but AT&T's looking to prove us wrong with a series of new add-ons available with its GoPhone service. Customers can now tack on 3,000 off-peak minutes for $20, messaging plans ranging from 200 messages for $5 up to 3,000 for $20, and a pair of data plans: 1MB for $1 and 5MB for $5. With us so far? Good, but here's where it gets kinda weird: the 3,000 off-peak minute package can only be added for GoPhone customers paying the optional $1 / day fee to lower their per-minute talk rates from 25 cents to 10 cents. AT&T's billing the data as the only prepaid data packages among major competitors, so we figure that's good news for the prepaid world -- we think, anyway, once we make sense of it all.