MySocialApp - Seamless Social Networking features for your app
Slackin - Create your own public Slack chat community
Manyverse - A social network off the grid
Message Bender - Backup and delete all Slack messages in bulk
Mastodon - Mastodon is a decentralized, open source social network. This is just one part of the network, run by the main developers of the project It is not focused on any particular niche interest - everyone is welcome!
Slack Archive - Public, searchable & browseable archive of Slack channels