Rarely, like once every couple months. When I do though, I get completely trashed. I almost always wake up feeling like an ******* / idiot.
Some examples... last time after getting herded out of the bar I went for a walk with my buddies along the beach (newport), and decided to be civil and use a bathroom to relieve myself. Well I went into a public restroom, a quite odd one that had no urinals and a lot of women in it. Naturally I yelled at them to get out of my bathroom, and midway through pissing away I realized I had walked into a women's bathroom. In another case I ripped the metal door of a newpaper dispense, took a couple of papers out and tried to sell them to pass bys. Why I don' know, at the time my buddies and I thought these things the funniest **** in the world, but I always wake up the next day feeling guilty, like a dog that just ate a wedding cake.
I don't ever wake up with hangovers / sickness though because one thing I learned @ a young age was that I could eat / drink endless quantities of just about anything when really drunk, so i take advantage of this by having a quart of water and a gram or two of Vitamin C right before I go to sleep. Usually some food too. Ever since I started doing this I always wake up feeling fine physically, but mentally I feel stupid for doing something that I know impedes my gym progress.