What do you consider a bargain in wine? Ten percent off? Twenty? How about 40? That was the discount that Wines Til Sold Out offered recently on 2006 Chateau Angelus, a top Bordeaux that was being sold for nearly $100 off its original price of about $250.Prices that seem too low to be true are typical of the dozen or so flash wine sale sites that have popped up over the past two years. The sites offer limited amounts of wines at discounts that are shockingly steep but highly temporary.