Six Excellent White Wines Under $20 (O.K., One You Have to Find on Sale)

I tasted these wines, which offer different sorts of charms, pleasures and virtues, last week, at home with various meals. The Bonny Doon Le Cigare Blanc 2005 and the Graff Family Vineyard Pinot Blanc 2005 were particularly good with wild Coho salmon, sauteed with nothing more than salt and pepper and a squeeze of lemon, but let's start with the wine th…