Of all the things you may have expected me to post, milk bottle caps probably isn't high on the list. But they fit the bill for lileks.com for two reasons: nifty old graphics, and symbols of something we don't have anymore.
The skirt above wasn't exactly a bottle cap; I imagine it was folded over the neck and cinched with a ring. I believe the triple S was a guarantee of Sanitation from Sealright Sanitary Service. Or it meant it was bottled in a facility that processed snakes.