I work on OpenBazaar and I'm happy to answer any questions.
The basics: It's a fully distributed network where people engage in trade directly with each other using cryptocurrency. Because there are no middlemen, there are no fees, there is no centralized data collection, there are no account sign ups, and there is no censorship.
You can view the server (Go) here:
https://github.com/OpenBazaar/openbazaar-go
And client here:
https://github.com/OpenBazaar/openbazaar-desktop