In 2009, the city’s planning commission noted that its hazy future, “combined with the social and physical isolation of the area from the rest of the city, attracted populations on the margins of mainstream America, such as artists, immigrants, radicals, and gays.” A 1976 photograph by Michael Jang shows a lone car in a parking lot as big as a prairie, with the towers of the Financial District on the horizon. This was once just plain South of Market, a vast area beloved mostly by those who like their cities underpopulated, run down, rule-free, and cheap. (I’m not really sure what happens when you toss all those terms into a pot and stir, but it seems to produce some moneymaking fumes.) What started out as the Transbay Transit Center now bears the name of an especially vaporous entity: Salesforce, a cloud-based software-as-a-service (SaaS) specialist in customer-relationship management (CRM). One offspring from this marriage of software and hard steel is the Transbay district, a frictionless, caffeinated neighborhood of fast elevators and lush plants that fans out from a new bus station designed by Pelli Clarke Pelli.

They’ve reshaped the skyline, transformed streets, boosted homelessness, and shifted commuting patterns. In San Francisco, tech companies have made every patch of dirt and square foot of flooring an ultraluxury commodity. In the past decade, businesses that lurk in the ether have had a profoundly concrete impact on cities - a few of them, anyway.

Salesforce terminal park