Bike Index
the internet's bike registry
Diaspora
community-run, distributed social-network
Discourse
next-generation discussion platform
Hitobito
full-scale group hierarchy management
Intercity
web-based Dokku deployment
lobsters
link-aggregation site, inspired by Hacker News
Mastodon
distributed, interconnected microblogging
Open-Source Event Manager
event management tool tailored to conferences
Pokr
agile estimating and planning
Punchclock
simple electronic punch clock
rubygems.org
The Ruby community's gem hosting service
TaxonWorks
workbench for biodiversity informatics
World Cube Association
everything for the World Cube Association