Huawei GTM900
Has serial port which takes AT commands. Easy enough to drive it.
Costs $20 a shot.
Have you tried one of these out? Where can you buy one?
http://www.rfsolutions.co.uk/acatalog/RFS_GSM_Modules.html
I have tried out. Well documented and you can get the breakout boards for $5 but I forget precisely where. Managed to get it working in UK on O2 pay as you go. Now in junk box :(
Watch out - you need a level shifter if you're using an Arduino or something as it has 3v3 operation. I used an old(er than me) HP lab PSU and a crudely hacked up set of BC548 switches as a level shifter. You need an antenna and a sim socket (my sim was cruely soldered onto 1/0.2 solid wire and plugged into the breakout board header).
oh god, thank you so so so so much for this.
You can hack this module: http://finch.am/projects/arduinogsm/ $25
OR you can buy this arduino shield: http://www.sparkfun.com/products/9607 $100
Re:Arduino Burglar Alarm Sends SMS
by revelation on Thursday May 03, 2012 @11:54AM
(#3924357)
If it doesn't have to be SMS only, there are various mass market "surf sticks" offered by providers on the cheap, marketed at laptop owners and the like. Many of them are just AT modems with serial ports tunneled through USB and then controlled by an application on the computer.
All the ones I have used were expensive industrial spec units with complex data channels.