From SAFCo Software:
No "credits" required. Sends truly free text messages (SMS) alert to one or multiple (blaster/bulk) cell phones from your desktop via the Internet. It is not necessary to know what their cell phone carrier is. Useful for schools, businesses, groups, organizations, clubs, offices, teams, or any one that needs to instantly send a message to multiple people. No cell phone is required to send messages. It has its own address book for ease of use. Supports command line operations. Messages can also be scheduled for later delivery, or set to repeat automatically. Supports most major USA and world carriers.
What's new in this version:
Version 6.1.6 is a bug-fixing release.