It’s a Siemens SX66. I reviewed it earlier this year. Read my review.
I’m posting this from it via my home wireless network.
Cingular has their own GPRS network, and I’ll use it in a pinch, but it’s really sssslllllooooowwww, not to mention expensive. I prefer other options.
It is very important that you password-protect your home wireless network. I bet there are scads of middle-aged women driving around looking for open wireless networks so that they can steal bandwidth.