I've been finding value in Facebook Marketplace recently. It's kind of a step up from craigslist- basically people on it are more willing to ship things to you and Facebook acts as a financial middleman. Facebook has been enforcing quality standards on the sellers- at least they will not pay the seller until a tracking number has been provided for shipped items. For buyers, the prices tends to be better than on eBay.

Anyway, they could give eBay some real competition and could be a future revenue source if it keeps expanding.