Appropriation-friendly collection of books, periodicals, and more.

This surreptitious shop is only open five hours per week.

This one-block alleyway is stuffed with street art that is colorful, cultural, and intensely political.

A free, public museum dedicated to the fascinating science of sight.

The miraculous hydrant that saved the Mission District in 1906.

The grand, column-fronted, sculpture-adorned home of the ambitious digital library.

One of the last remnants of the city's Chinese nightclub scene is now a dive bar selling killer mai tais.

Half of a house.

A promotional sun clock on the site of San Francisco's great raceway.

Tenacious mummies survived dental problems, eternal entombment, and more than their fair share of devastating fires.

This print shop boasts one of the largest pinball arcades in San Francisco.

This turn of the century masterpiece has a mysterious goaty interloper.

This concrete tangle of square pipes has stood as a proud thorn in the city's side since the '70s.

With the touch of a button, you can read a randomly selected short story.

A modern mechanical planetary system, part of a 10,000 year clock.

The randomness of this wall of lava lamps helps encrypt up to 10 percent of the internet.

A shop full of natural curiosities, carnivorous plants, and costumed taxidermied mice.

If it hadn't been caught in time, a flaw in the design of this Manhattan skyscraper could have led to its collapse.

Once a flowing stream and where the USS Monitor, the world's first ironclad, was built and launched.

The childhood home of one of America's greatest unsung troubadours still stands in a much changed Brooklyn neighborhood.

A group dedicated to promoting boating, kayaking and environmental education programs.

Fabrication workshop where the encasement for One World Trade Center's beacon was constructed.

The rare American Civil War-era weapon was never fired in anger.

After surviving abandonment, this powerful Latin American mural is alive again.