Interesting in this context is completely divorced from morally good/bad. Could be any group from any area at any time in history. I’ll start with a few, followers of the cult of pythagoras, contemporary black Hebrew Israelites, antiracist skinheads and the Amish (neo-luddites in general). Don’t be racist or a prick to other people discussing.
The free masons originally grew as a support and trust network.
It used to be that traveling was FAR less common. Consequently, travellers were seen as suspect. One of the major exceptions was masons. They would have to relocate to big projects e.g. a castle. They would stay long enough that the lack of trust was a problem, but not long enough to properly overcome it.
End result, they started vouching for each other. A local groups would vouch for the newcomers. They would introduce them and stop them getting ripped off.
Furthermore, stonemasonry was a dangerous trade. It was easy for a mason to be killed far from home. They clubbed together to support the families of members, as well as the disabled.
Wrap this up in Christianity based traditions and you have the masonic free masons. An early cooperative support and social networking group.