Permanent Shift
Permanent Storage
No inflation - All storage is paid upfront for 250 years.
Legal
Arweave contains a legal protocol, for a tracable distributed removal of content on a geolocation basis.
Getting technical
Instead of calculating some random number - as bitcoin does, Arweave calculate hashes of 256 kilo bytes chunks of real data,.
As a proof of work - Arweave provides a distributed global storage service.