I'm riding a 'bent when I do touring now, so I've got it easy. I use a pair of convertible fishing pants. (supplex nylon so they wick and dry fast, legs zip on and off). I wear a set of UnderArmor Sport Briefs, (same concept as the ex-officio). Works like a charm for me, cuts down the amount of clothes that I have to carry, since my biking and off-bike clothes are the same.
M58