In the course of turning the F3 into a really functional collaboration platform, I recently activated the latest mailing list features of the Discourse software here on the F3. You can now reply to forum posts you get in your inbox simply by replying to them. Also, you can post new topics in specific categories by sending to very specific email addresses. Note that for this to work, you must send your mail from the email address that you used to register your forum account!
In other words: The Discourse forum software is now more useful and powerful than Google Groups! And the F3 fully profits from that. 
Here are the specific email addresses for the different categories:
- Visions: fractalfuture.discourse+visions@gmail.com
- Netec: fractalfuture.discourse+netec@gmail.com
- Projects: fractalfuture.discourse+projects@gmail.com
- Fractal Cosmos: fractalfuture.discourse+cosmos@gmail.com
- DIgital Abundance Network: fractalfuture.discourse+dan@gmail.com
- Internet of Thinkers: fractalfuture.discourse+iothinkers@gmail.com
- Ideas: fractalfuture.discourse+ideas@gmail.com
- Hypercube@SOHOland: fractalfuture.discourse+hypercube@gmail.com
- Quantified Prestige: fractalfuture.discourse+qp@gmail.com
- Discourse: fractalfuture.discourse+discourse@gmail.com
- Society: fractalfuture.discourse+society@gmail.com
- Science & Technology: fractalfuture.discourse+scitech@gmail.com
- Personal Development: fractalfuture.discourse+pd@gmail.com
- Philosophy: fractalfuture.discourse+philosophy@gmail.com
- Basic Income: fractalfuture.discourse+ubi@gmail.com
- Café: fractalfuture.discourse+cafe@gmail.com
- Communities: fractalfuture.discourse+communities@gmail.com
- Transhumanist Parties: fractalfuture.discourse+tp@gmail.com
- Transhumanist Party Virtual: fractalfuture.discourse+tpv@gmail.com
- Transpolitica: fractalfuture.discourse+transpolitica@gmail.com
- Deutsch (German): fractalfuture.discourse+deutsch@gmail.com
- Meta: fractalfuture.discourse+meta@gmail.com
- Uncategorized: fractalfuture.discourse@gmail.com
Btw: I’ve found out that the email "fractalfuture@gmail.com" and the Twitter handle “@fractalfuture” seem to be taken by some minor unknown company. That’s the reason I’ve registered "fractalfuture.discourse@gmail.com" instead.