I want to share some of the recommendations with you (the FSF concentrates on Free as in libre Software for all OS, not just for Linux, of course):
I hope there is one or the other software that now interests you. I will check out some of the mentioned myself.Chat
When we can no longer communicate face-to-face, tools for voice and video calling often come to mind as the next best thing. But as evidenced by the size and success of the proprietary software companies that sponsor these tools, their development isn't easy. Promoting real-time voice and video chat clients remains a High Priority Project of ours. Though we may still be waiting for a truly perfect solution, there are some projects that are far enough along in their development that we can recommend them to others.
Mumble: Mumble is a real-time, low latency program for hosting and joining audio conversations. Clients are available for every major operating system, and even large rooms tend not to put too much stress on the network. When it was time for us to go fully remote, the FSF staff turned to Mumble as a way to have that "in-office" feel, staying in touch in rooms dedicated to each of our teams and a general purpose "water cooler" room.
Asterisk/SIP: When we give tours of the FSF office, people often think we're joking when we mention that even the FSF's conference phones run free software. But through Asterisk and our use of the SIP protocol, it's entirely true. Although it can be difficult to set up, it's worth mentioning that free software can manage your traditional phone lines, and even transfer calls seamlessly to digital extensions or SIP clients like Jami and Linphone.
Video calls and presentations
Jitsi: Jitsi was a key part of LibrePlanet 2020's success. Providing video and voice calls through the browser via WebRTC, it also allows for presenters to share their screen in a similar way to Zoom. And unlike Zoom, it doesn't come with serious privacy violations or threats to user freedom. The connection between callers is direct and intuitive, but a central server is still required to coordinate callers and rooms. Some of these, like the Jitsi project's own "Jitsi Meet" server, recommend proprietary browser extensions and document sharing tools. If you're able, hosting your own instance is the most free and reliable method.
OBS: Another much-used software program this LibrePlanet was OBS Studio. Illness, different timezones, or unforeseen travel were no match for the solutions that OBS Studio offered. It's a flexible tool for streaming video from multiple inputs to a Web source, whether that's combining your webcam with conference slides, or even your favorite free software game. At LibrePlanet, OBS allowed our remote speakers to record their presentations while speaking in one screen, and sharing audiovisual materials in a second window.
XMPP: If you've ever used "Jabber," older iterations of Google Talk or Facebook Messenger, then you've used XMPP. XMPP is a flexible and extensible instant messaging protocol that's lately seen a resurgence from clients like Conversations.im and encryption schema like OMEMO. XMPP is the instant messaging method we prefer at the FSF when we need to discuss something privately, or in a secure group chat, as everything is sent through servers we control and encrypted against individual staff members' private key. Also, access to the FSF XMPP server is one of the many benefits of our associate membership program.
IRC: Messaging services have become all the rage in office atmospheres, but nothing about Messenger or Slack is new. In fact, Slack (and its counterpart for video games, Discord) takes more than a few cues from the venerable Internet Relay Chat (IRC). IRC remains an enduring way to have a text-based chat in real-time, and as evidenced by Web clients like The Lounge, or desktop clients like Pidgin, it can be as stripped down or feature-rich as you like. For a true hacker experience, you can also log into IRC using Emacs.
Encrypted email: While it's asynchronous and maybe the most "old school" item on our list, GPG-encrypted email is a core part of the FSF workflow, and helps guard against prying eyes, whether they're one room over or in an NSA compound across the country. The initial setup can sometimes be a challenge, which is why we provide the Email Self-Defense Guide to get you up and running.
Discourse: Discourse is the message board software that powers the FSF associate member forum, and we couldn't be happier to recommend it. While the concept may seem a little antiquated, message boards remain a good way to coordinate discussions on a particular topic. Discourse's moderation tools are intuitive and easy to use, and it even includes achievements for users to earn!
If you're unused to working remotely, finding ways to collaborate with others on a document or presentation can be a challenge. At the FSF, Etherpad is the main tool that we use to keep live meeting notes and work together on other documents. It provides all the features you need for quick collaboration, including comments, revision tracking, and exports to a variety of formats. You can host your own instance, or you can select an instance made available by others and start sharing.
At the FSF office, we have a common server to store our files. Not everyone has the luxury of a setup like that, and especially not due to the fast changeover from office to home. To avoid using proprietary "solutions" and disservices like Dropbox, you can turn to the widely popular Nextcloud to synchronize your text and email messages, share calendars with coworkers, and exchange files privately with your friends.
If you need something temporary, there's always Up1. Up1 is a temporary, encrypted text and image sharing program you can host locally, making sure those files you need to exchange are only there for just as long as it takes for your friend to download them. And while we don't use it ourselves, we've heard good things about the Riseup network's instance of Up1, and will occasionally suggest it to those wanting a quick and easy way to share files while retaining their freedom.
This is just a small selection of the huge amount of free software out there, all ready to be used, shared, and improved by the community. For more suggestions on both local and Web-based programs, visit the FSF's Free Software Directory, our volunteer-run wiki which aims to be a comprehensive list of the thousands of free programs available for everyday use.