There’s definitely no shortage of Duane Reades, Starbucks, and banks lining Manhattan’s streets, but other than these national chains, it’s hard for small business ownersto affordthe city’s soaring commercial rents, and these mom-and-pops are currently lacking anyprotections from landlords. In some areas, this has created achain store monopoly, while in others it’s left stretches of otherwise popular streets with large numbers of vacant storefronts. ProgrammerJustin Levinson is exploring the latterthrough a new map calledVacant New York, which provides a startling picture of Manhattan’s shuttered storefronts and itshigh-rent blight.