How I (try to) organize my collection, a presentation I gave at my former employer
Repairing Retro-Hardware, a presentation I gave at the 13th Zurich Hardware Meetup
Results of a Feb 2023 study (PDF) sponsored by Bundesamt für Umwelt on reusability of electronic devices deposited for recycling (outdated project page)
Mobile Recycling stations in Zürich offer a "Tauschplatz" where your unwanted-but-working stuff can get a last chance to find a new owner before getting recycled
Dedicated retro repositories: oldcrap, oldcomputers, minuszerodegrees, The Retro Web
These are amazing, lots of otherwise lost documentation and software is archived there.
Retro-YouTube channels that are great for learning general technique: Adrian’s digital basement, EEVblog, LGR, Tech Tangents, RMC - The Cave, My Mate Vince, CuriousMarc