What are Paperclip groups and why should I join them?

Paperclip groups are your very own micro marketplaces based around a particular hobby, interest, or place.

Let's say you are into scuba diving, you could join a nationwide scuba group or a local one for your scuba center. This group would be dedicated to buying, selling, swapping, and freecylcing scuba equipment. If you have any scuba gear you dont want anymore you can add it to this group and you will have a better chance of selling it because everyone else in that group loves scuba diving. You also know that if you need a piece of scuba equipment you can turn to this group, if its not there then send a request to the group, everyone will see it and someone will respond to you. 

Joining group adds that extra layer of confidence that you are going to find or sell an item because you are trading with likeminded people.