Classified ads is internet communications program that works in distributed manner, requiring and supporting no concept of "server". Classified ads supports

Concept of operator, that is identified by encryption key and can contain also other data like real name that human being operating the profile wants to publish.
Making some data available to listed operators only, this is done by marking a operator profile private.
Sending and receiving
1. Public messages, that are called "classified ads" due to classification that they carry,
2. Private messages between operators,
3. Comments regarding operators, readable by group that see profile of the commented operator.
Basic word-based search functions.
Voice calls between operator nodes.

For more information see http://katiska.org/classified-ads/. In order to use classified ads in meaningful manner, user needs to have the operated instance of this program to connect to some other program instance over some network. Classified ads tries to do that automatically but it may be necessary to ask for network address of node operated by a friend to get connected and started.

Classified ads is released under LGPL license.