This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American
Thrifty Thursdays feature photographs taken with equipment costing less than $500.
Easy-clean surfaces are tough on bar bathroom graffiti. Scrawlings that aspire to permanence retreat to the tiny writable spaces between the tiles. It's a natural selection of sorts.
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This particular message was inscribed above a urinal in Urbana, Illinois. As this was not a place I normally hang around with professional SLR gear, my iPhone 4S came to the rescue.