+ - store individual messages
+ - where?
+ - something like DBM or SQLite - faster
+ - filesystem - transparent, easily published - probably best
+ - [ ] block(chain/tree) of twtxts
+ - distributed twtxt.db
+ - each twtxt.txt is a ledger
+ - peers can verify states of ledgers
+ - peers can publish known nick->url mappings
+ - peers can vote on nick->url mappings
+ - we could break time periods into blocks
+ - how to handle the facts that many(most?) twtxt are unseen by peers
+ - longest X wins?