Alaveteli
easy FOIA requests for any jurisdiction
Coyote
image annotation
Discourse
next-generation discussion platform
Errbit
open source, self-hosted error catcher
Feedbin
open-source feed reader for multiple platforms
iNaturalist.org
social network for nature stuff
lobsters
link-aggregation site, inspired by Hacker News
Mastodon
distributed, interconnected microblogging
Notebook.ai
structured writing tool
openstreetmap.org
crowd-sourced map of the world
Organization for Transformative Works Archive
archives of fanworks, including fanfic, fanart, and fan vids
Texterify.com
translation and localization management
Tracks
software for implementing David Allen's Getting Things Done™ methodology
zammad
enterprise-ready helpdesk and customer support system