As I mentioned last week, we're looking into using SMS in countries like Nigeria to transfer data between remote schools and central administration. This is the easiest and cheapest way to do it in the poorest countries in the world.
Whether or not it is the easiest and cheapest way to do it in the US is a different question, especially if you're a cell-phone luddite who ostentatiously parades around his Old Man Phone, on the rare occasions he can find it and/or its charger, and it is actually charged. Needless to say, the Old Man Phone doesn't do SMS or Bluetooth. Strictly speaking, I don't ever have to get this functionality working on my computer, but I'll never fully understand it if I don't have a little hands on experience myself.
So... what you need is a phone with Bluetooth support, in particular one which supports the Dial Up Networking (DUN) service over Bluetooth. In theory you could also send SMS's using your PC through a USB connection, but I'm using Linux, and there are probably no drivers for your controlling particular phone via USB on Linux. Bluetooth is at least a standard interface.
The problem is that US carriers don't like to leave DUN on. It is what allows you to "tether" your phone. If you have a data plan, that's what you'd use to connect your laptop to the internet via the phone. The carriers don't want you to do that. They want to sell separate services, so they disable DUN in software. That's why in the US you can't tether your iPhone but you can almost everywhere else.
In this case, I don't even want to access the internet via DUN, I just want to send an SMS. In fact, I shouldn't even need a data plan for it to work, just a voice and SMS account.
So what I need is the cheapest possible phone that I can get without a long-term commitment, e.g. a pre-paid burner, that supports DUN over Bluetooth.
I imagine this is possible, and I'm sure I could have done it with my goofy old N-Gage, before I lost it, but at this point it is like looking for a needle in a haystack. There are also other possibilities which might work like buying a generic modem and trying to stick a pay-as-you-go SIM card in, but they all involve spending about $100 to try the experiment. I could, of course, just buy a cellular modem with a two year commitment, but that's expensive and I generally don't need it. I could just give in and buy a modern phone, but what I'd want then is an iPhone or good Android phone, which also don't support DUN without being rooted, so it still doesn't really solve my problem.
Also, all of the above may be wrong, because I really don't understand this shit.