I didn’t have a cell phone until this time last year. Same as you, I really don’t think there’s that much that can’t wait until I get home or back to my desk. Work wants me to carry a cell or a pager, but thankfully only calls me on it a couple times a week.
But my wife pestered me about it (for about five years), so I ended up putting a pay as you go SIM card into her old flip phone. 11 months into the phone, I think I’ve used $75 worth of minutes (about an hour of talking a month). It probably helps that I leave it home or don’t notice that it’s out of charge about a quarter of the time. However, our first son is due in a couple weeks, so I actually am keeping it charged this month 🙂