I found a clever spreadsheet that can calculate your BAC (blood alcohol content), and work it out how it drops off over time. Not sure how accurate it is, but it seems to work for me.
I set up the NWA case mentioned by Tower Dogs (19 rum and cokes), and it's evident that one would still be drunk the next morning.
BAC calculator
Someone just needs to reprogramme it to be able to calculate in litre size steins of beer and then its sehr gut!