  We discuss several uses of blockchain (and, more generally, distributed
ledger) technologies outside of cryptocurrencies with a pragmatic view. We
mostly focus on three areas: the role of coin economies for what we refer to as
data malls (specialized data marketplaces); data provenance (a historical
record of data and its origins); and what we term keyless payments (made
without having to know other users' cryptographic keys). We also discuss voting
and other areas, and give a sizable list of academic and nonacademic
references.
