I didn't get one of the XDA versions sold by phone companies, but I have a Ipaq 5450 with an expansion pack and a CDMA phone card from Verison w/ an unlimited time, 115 Kb/s connection and voice service for $80/mo.
After the current contract ends I will probably switch over to T-Mobiles GSM setup. I has similar speed and they recently started offering an all you can eat internet plan and voice service for less than I am paying now. And with a triple band card I can use the phone while in Europe (and most of the rest of the world)which I can't do now with CDMA.
As a matter of fact I have the wireless card my laptop as I am writing this. I get access times that are better than dialup/worse than cable (in the ISDN range) and its portable (mostly, you have to watch out for dead spots. There are areas that I can make a phone call but not data calls).