Web Applications
Check out ownCloud. These services are available to everyone who has a shell, regular dial-up, dsl, or web hosting account here. It is a federated services allowing you to share files with anyone anywhere. It also has a number of cloud applications, calendar, contacts, mail, etc.
We have ditched phpbb3 in favor of friendica, hubzilla, and mastodon social media sites. The advantage of these is that they are federated, that is messages are distributed to tens of thousands of nodes around the world.