I know people on .com seller forums are talking about supporting each other by making collections and pinning an ad of each others to their collections, and posts collections on Pinterest and Facebook to generate extra interest. I've started a collection being of jan and its of my favorite sellers & coins, with a few of my items added. As you can share your collection and people do look at others collections. It's an interesting way to promote your sales. Some of the more ambitious ones even make a Facebook or twitter account to promote their collections. This is all done on the.com site. I think it's a great tool, I just need to learn how to do it effectively.