I found a neat hack that allows a Arduino to call out, as well as receive communication from the open source Linux PBX, Asterisk.
I’ve been able to get Asterisk grab info about sensors connected to an ethernet-enabled Arduino, but how about the other way around? What if you could allow your Arduino to make outbound calls through your Asterisk system to make a make-shift alarm system, or over-powered doorbell?
Read more at http://www.nerdybynature.com/index.php/2010/09/br-r-r-r-r-ing-its-your-arduino/, and watch the video!
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