Create an email group, that’s an unique email address which will distribute emails to all of the addresses in the group (alternative to Google Groups).
In addition to @:meta.F, the non-profit association leading the campaign described here, we may also mention <a href="http://april.org">l’April</a>, <a href="http://laquadrature.net">la Quadrature du Net</a> or <a href="http://aful.org">l’Aful</a>. These organizations can only keep going with the help of your donations, so don’t forget to support them!
Online services are often closed-source: once you start using them, it is very difficult to leave, because these companies do everything to keep you captive by preventing you, for example, from migrating your data elsewhere.
Using open source services means making sure that you will never be controlled by a particular website, but also that you can always migrate your data elsewhere.
Centralized services raise many problems: they make your data very vulnerable (one inaccessible website and everything is down) and make it very easy for third parties to exploit your data.
Using decentralized online services means maintaining a choice between using an online resource such as those offered by Framasoft or installing/managing the service yourself.