I’ve now installed a microscopy forum which adds an extra level of organization by pre-defining certain categories. It is also not necessary to register in order to use the forum.
While mailing list services (such as the amateur microscopy group in Yahoo Groups) is a great installment, I found it difficult to find things that I’m looking for. This is due to the organization of the mailing list. There are individual threads and as soon as the discussion of a topic is finished, the thread starts to move into the background and quickly disappears out of sight.
It can take time until there are enough forum posts. I therefore encourage everyone to contribute to the forum, to make it an active platform for enthusiast microscopists.