Satellite Communications
Satellite has enjoyed a huge resurgence as a disaster recovery technology, since it is often the only service available after a widespread disaster such a hurricane or tsunami. One technology that we really like is kind of a "PRI on the fly." The idea is to connect a Primary Rate Interface (PRI), also known as a "smart T1," to a satellite link.
At this point, you might object on the grounds that typical data rates over satellite are only about 256 kilobits per second (Kbps), whereas PRI is 1.536 megabits per second (Mbps). This is true if you use 64 Kbps channels, but you don't need all that bandwidth just to carry voice. With today's technology, you only need 1/6 of the bandwidth to carry this hypothetical PRI, and that's still more than enough for good voice quality. Hence, you get 1.536 Mbps of voice capacity for the cost of 256 Kbps.
A couple of companies have even married this capability to a PBX. Telecom Recovery and Rentsys Recovery Services offer boxes that convert raw satellite bandwidth to the four-wire circuit and PRI signaling that your PBX expects to see. If you can restore a single PRI and its associated direct inward-dial (DID) numbers to a medium-sized hospital, for example, for all practical purposes you have restored communications to that hospital. The same goes for government offices, businesses, and essential services. That's why we think that this particular "PRI on the fly" idea is really cool. Combined with a good outbound notification/emergency communication system as previously described, this setup is just awesome.