This is the number that our chior director uses to call all choir members to give them informative information such as what we are singing on Sunday. I think it is great for this purpose. I suppose anyone who needs to do mass calling could use it.
This is Calling Post. Companies use this service to make thousands of calls with pre-recorded messages. it's popular among churches, non-profits, and other groups.
3rd part dialer service, "Calling Post" www.callingpost.com I think they are somewhat reputable but their clients arent. Call their service number at 1-877-665-5646 and they will quickly and courteously block you from all their clients.