I enjoyed this fun Atlantic Wire post on shopping under the influence.
I have been to enough Palm Beach charity events over the years to understand the silent auction (and live auction) bidding dollars go way up the more people drink.
As such, I would add a section to the article that one should generally get a pass for shopping/bidding at charity auctions, since its for charity.
Otherwise, I thought the suggestions in this guide were great. Definitely leave the credit cards at home if you are shopping after drinking and have a friend there to talk you out of bad ideas.
I often find myself in trouble when it comes to art, because (1) I love original art, (2) I'll spend good money for art, and (3) I'm often admiring art while holding a glass of wine. So I stick to my rules and anything over a $100 requires a cooling off period. I'll take a photo of the art with my iPhone, I'll take a business card, but I generally don't buy art on a first viewing.