I'll normally have one pint of ordinary strength lager at the very beginning of the night. (Note to all at Plasa: CARLING

)
But after that its my trusty 2-litre bottle of Diet coke. Partly due to it being refreshing etc..etc.. but also the bars at some places are so packed, you wont get served before its time to start the next track...so having your own supply of refreshments is a must.
Staff parties, after the punters have gone, is another matter, expecially if I've got a free room for the night...
One venue that I do regularly (hotel), the barman brings a drink out to me hourly, and I make sure that its only pints of "kalibar" or Red-bull, coke etc.
Back to topic...Hmmm I do recall that at one particularly lengthy do, I completely lost my place in the toasting/Master of Ceremony annoucements about who was supposed to toast who after who had said what about who...(exactly

) and of course, everyone turned to me as I announced a request for silence for a reply from the wrong right honourable be-chained whoever....
I covered it with something like "Well, to err is human, so at least you know Im not a robot, where did we get to?" and someone got me back on track.
An old fellow agency DJ, who I worked with years ago, once announced "Jazz funk" over a cheap mic, and promptly got verbally "poked" by about 3 old dears...telling him not to swear...
oh and never ever get roped into introducing "Mandy is wearing the latest Jaeger silk blouse, in peach blossom white..." etc at wedding fairs...you normally end up going through ALMOST the same speil 3 times per afternoon, only to find that some bridal wear manageress has changed the running order of the girls she's sending out to the catwalk, but hasnt told you.... I now verbally check the running order with the heads of any participants prior to each catwalk display...this eliminates you saying "Janice is showing us this fine green satin...." etc....when someone struts onto the catwalk in a pale BLUE outfit...." DOH!