I have read that sleep deprivation is as bad as getting drunk in terms of the number of IQ points' hit taken, so I would argue that many folks in the industry are effectively coding drunk :-)
I drunk code often enough. One thing I've learned is to make a backup of whatever I'm working on and put it somewhere out of easy reach (be it on a remote server, or a flash drive that is removed from the machine.) You will inevitably break something, but I typically come up with more gold than overall damage.
it depends, for some critical line of code you can't make mistakes (for example if you are writing something involved with security , or in some worse case if you are programming an airplane consolle). So my point is: you can be drunk while coding but you have to be 100% sober while planning your tests for that code. Accordingly to a lot of studies alchool (also drugs) helps our brain to "think different" so while you are drunk you could find a solution for a problem you were stuck in just because while you are drunk your brain discovers different patterns. However i don't have much experience about this ... i've coded something while i was mildly drunk and i saw no difference.
I am part of the Friday Club at work, basically we have about 3/4 pints every Friday lunch time. My output on a Friday afternoon is close to zero, I cannot concentrate and really don't recommend it!
I had a co-worker who coded his own CMS for a relatively successful web agency (it was the pre-wordpress era). And he coded part of this CMS on paper at a party. Must have been one crazy party :)
