Bluetooth XMPP Doorbell
Here is a doorbell that make from a bluetooth mouse by using XMPP protocal(XMPP or Extensible Messaging and Presence Protocol is a protocol based on Extensible Markup Language (XML) and intended for instant messaging (IM) and online presence detection. It functions between or among servers, and facilitates near-real-time operation. The protocol may eventually allow Internet users to send instant messages to anyone else on the Internet, regardless of differences in operating systems and browsers.)The source code programming with python and the code is very very basic
   Bluetooth XMPP Doorbell
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