A truenumber is a single, immutable data value that carries a description of itself encrypted inside. It can migrate from one document to another, live in a spreadsheet and a database too. You can't be more decentralized than that! A truenumber's meaning and validity are locally assured by encryption and hashing, but if you need a foolproof guarantee - it can be signed and stored on the Etherium blockchain.
Data in this form is disruptive to existing information technologies because even a spreadsheet containing truenumbers has more traceability and authority than any enterprise database application can possibly have. Truenumbers is the simplest, most generally useful application of blockchain there is - and is available now, for data big and small.