The Web is a key space for civic debate and the current battleground for protecting freedom of expression. However, since its development, the Web has steadily evolved into an ecosystem of large, corporate-controlled mega-platforms which intermediate speech online. In many ways this has been a positive development; these platforms improved usability and enabled billions of people to publish and discover content without having to become experts on the Web’s intricate protocols. But in other ways this development is alarming. Just a few large platforms drive most traffic to online news sources in the U.S., and thus have enormous influence over what sources of information the public consumes on a daily basis. The existence of these consolidated points of control is troubling for many reasons. A small number of stakeholders end up having outsized influence over the content the public can create and consume. This leads to problems ranging from censorship at the behest of national governments to more subtle, perhaps even unintentional, bias in the curation of content users see based on opaque, unaudited curation algorithms. The platforms that host our networked public sphere and inform us about the world are unelected, unaccountable, and often impossible to audit or oversee. At the same time, there is growing excitement around the area of decentralized systems, which have grown in prominence over the past decade thanks to the popularity of the cryptocurrency Bitcoin. Bitcoin is a payment system that has no central points of control, and uses a novel peer-to-peer network protocol to agree on a distributed ledger of transactions, the blockchain. Bitcoin paints a picture of a world where untrusted networks of computers can coordinate to provide important infrastructure, like verifiable identity and distributed storage. Advocates of these decentralized systems propose related technology as the way forward to “re-decentralize” the Web, by shifting publishing and discovery out of the hands of a few corporations, and back into the hands of users. These types of code-based, structural interventions are appealing because in theory, they are less corruptible and resistant to corporate or political regulation. Surprisingly, low-level, decentralized systems don’t necessarily translate into decreased market consolidation around user-facing mega-platforms. In this report, we explore two important ways structurally decentralized systems could help address the risks of mega-platform consolidation: First, these systems can help users directly publish and discover content directly, without intermediaries, and thus without censorship. All of the systems we evaluate advertise censorship-resistance as a major benefit. Second, these systems could indirectly enable greater competition and user choice, by lowering the barrier to entry for new platforms. As it stands, it is difficult for users to switch between platforms (they must recreate all their data when moving to a new service) and most mega-platforms do not interoperate, so switching means leaving behind your social network. Some systems we evaluate directly address the issues of data portability and interoperability in an effort to support greater competition.