Other than the Steem DAO, which was forked (along with the rest of Steem) to become the Hive DAO, which has had much more active development since, are there any examples of successful, non-trivial DAO's?
There is a list on wikipedia here, including Dash, The DAO (which was a catastrophe) and Augur. Bitshares is not on the list but perhaps should be.
Are there any other examples of DAO's that actually function, are genuinely decentralized, and have an impact in some form (even if just financially)?
Despite its simplicity, and its weighting in favor of control by the larger stakeholders, it's my view that the Hive DAO is a truly radical development, particularly in its connection to HBD.
You might ask, what is so special and radical about it? It's that it is enabling the incentivized co-operation of a disparate group of people, whom have minimal relationships, but are financially aligned by stake in the Hive network. At the moment, that is allowing the DAO to function as a sort of decentralized central bank, implementing monetary policy. The potential of which really can't be overstated.