I bought a $15 Samsung flip for Verizon prepaid last night. It's mostly so I can take credit cards on my Epic over the phone (that whole CDMA issue).
It's the most basic thing but it has a calendar, memo, calculator, and email. It even has web access and verizon navigator. Obviously some of these things cost either in a direct fee or the data requirement.
Obviously I'm not getting rid of the smart phone because of the CC apps, but I probably won't jump on a new one every two years anymore either.