If you are registered, you get access to the members only section, can participate in the buy & sell second hand forum and last but not least you can reserve your preferred username before someone else takes it.
I have long enjoyed using old, manual film-era lenses on digital cameras and one of the main reasons for changing to FF mirrorless was to be able to use my collection of old lenses with their originally-intended field of view and focus them easily. I know there must be many like-minded people...