One advice I give to job market candidates is to make sure they do not drink to much at dinner, or they may say stupid things. It turns out I may be wrong on that one.
Jan Heufer makes the point that being drunk or under the influence of a drug is a very good commitment device if you are trying to show truth telling. He finds that this is a possibly good argument for the legalization of some drug that is not addictive if consumed in moderate quantitites. There is a loss of efficiency because people are sometimes under the influence, but there is a gain because better contracts are written.