iavatar - Self-Hosted, Federated Gravatar Alternative
iavatar is the software which libravatar runs on:
Libravatar is a service which delivers your avatar (profile picture) to other websites. If you create an account with us, your photo could start popping up next to forum posts or blog comments on any site where you left your email address.
There may be some great potential for integration with the LDAP/SSO functionality of Cloudron to provide avatar/profile images for services which support libravatar, too.