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How Signal walks the line between anarchism and pragmatism
(www.wired.com)
This is a most excellent place for technology news and articles.
A bunch of Matrix bridges on one platform, with some extra funding. It looks cool, but isn't lifechanging. It is designed to (hopefully) make it easier to use, but if you don't care, you can set up the bridges yourself on your own matrix server.
I'm surprised it's possible to talk to most of those services without having access to trade secrets. I guess you can get that info from reverse engineering the clients, but I'd expect that approach to be very brittle and possibly subject to legal action.