Is there a hash algorithm that allows generating currencies on demand, i.e. without the need of mining? For example, suppose there is a currency named "ODC" and the issuing authority wants to immediately generate new 1000 ODC units, is this possible given any of the current algorithms?

At around 12:00 am (GMT) my hashrates dropped by 1-2 MH/card in all my rigs!

Does this has something to do with the DAG drop we have been hearing about?

BTW, some of my rigs run the new beta drive from AMD (for blockchain) and they also suffer from this hashrate drop.