atTalk is a very simple end to end encrypted command line chat client in hommage to Unix talk.
You need to put you @.atKeys file in ~/.atsign/keys and then run the dart program detailing your and the remote atSign you want to chat with.
dart bin/at_talk.dart -a "@colin" -t "@kevin"
The person who want to atTalk with will have to do the same but in reverse
dart bin/at_talk.dart -a "@kevin" -t "@colin"