A large number of these installations are in the SoMa neighborhood, with one being particularly suited to San Francisco: the Murmur Wall. Designed by Future Cities Lab and installed outside the Yerba Buena Center for the Arts, the 60-foot Murmur Wall is a mass of steel and acrylic tubing, LED lights and digital displays. The bent steel tubes bring to mind the bicycle racks dotted throughout the city, but the installation's technology brings a decidedly more modern and social aspect to the art. Intermingling with the steel are a number of LED light tubes that lead into a series of screens at the piece's center -- and using your smartphone, you can send a short text message to the wall that'll display on the tubes.

Once your message has been submitted, you'll see a blue ball of light make its way from the left side of the display to the screens, where it briefly scrolls across. Once the message leaves one of the screens, you can again follow the ball of light as it makes its way through more LED tubes and shows up on more displays before it finally exits the installation entirely.

Messages from passers-by aren't the only things the Murmur Wall displays -- the project also taps into Google and Twitter and shows trending topics on its screens, signified by yellow balls of light. When I checked out the installation in late May, the Golden State Warriors were in the thick of the playoffs and numerous messages relating to the team flashed on the wall, both from individuals as well as the trending-topic algorithm the artwork uses.

While the value of the short snippets of text floating across the screen may be debatable, there's something very tranquil about watching the lights and words move from one end of the structure to the other. It's an engaging piece of artwork even without the intention of tapping into things trending around the city. And while not everything that flashed across the screen was worth noting, there were several times when the messages or trends coming through felt relevant, timely or interesting to read.

Just behind the Murmur Wall is another exhibit by Future Cities Lab that also integrates the city around it, albeit in a more organic way. Lightswarm is a collection of 430 light modules connected together and hooked up to sensors that measure and respond to ambient noise around the structure. The light modules themselves are all mounted on the walls of the Yerba Buena Center, and the sensors take the sounds from outside the building and translate them into different patterns that are displayed on the wall.

In a crowded city, it's sometimes difficult to determine what sounds the wall is actually reflecting -- but come nighttime, it's actually pretty quiet down by Yerba Buena. Once the sun starts dipping down, a group of friends' chattering is reflected in the movements of the light on the Lightswarm sculpture as they walk by. You can walk right up to the glass wall and tap on it to see how the sculpture reacts. Given the size of Lightswarm, it's tricky to tell exactly how the sounds of the city affect the lights, but the wave-like shape of the 3D-printed parts and their pulsing colors give the viewer a sense of calm in the middle of a busy neighborhood.

Bayview Rise, by Haddad / Drugan

While Lightswarm and the Murmur Wall are best seen at night, the huge, illuminated Bayview Rise mural is equally worth experiencing during the daytime. Located in the Bayview neighborhood in San Francisco's southeast corner, the illuminated animated mural was built on the city of grain silos. From a long distance, like on the highways that snake past the painting, you can get a sense of the full image, while up close you can appreciate the more abstract details that make up the composition. At night, the image really comes to life thanks to changing lighting that gives the mural an entirely different feel.

"We do site-specific public art and it's mostly exterior, often incorporating nighttime lighting," says Laura Haddad of her work with partner Tom Drugan. "We try to do it in a way that isn't just illuminating a sculpture so you can see it at night but adding another layer of meaning to the artwork." Between viewing the mural from afar or up close and during the day vs. night, there are definitely a lot of ways to take in Haddad and Drugan's artwork.

The project came about from an open call for artists from the port of San Francisco in 2013, and at the time Haddad was experimenting with how various colored lights would change the look of different colored images. The idea of using the side of the silo as a canvas for the new technique came up pretty quickly, so she put together a quick demo to test it out. "We made a quick video of an 11-x-17 colored print with LEDs cycling through," she says. "It was really effective, how the images changed with the light."

Beyond getting the interplay between the light and mural just right, Haddad and Drugan also wanted to make sure they made a piece of art representative of the neighborhood. "I lived in San Francisco in the '90s but didn't really didn't go to that neighborhood much," Haddad says. "But the port wanted to do something there for the community and give them a landmark," she explains.

To capture the vibe of the area, Haddad says they took a number of meetings with community leaders to get the pulse of the neighborhood; the mural itself contained a number of symbols of the area to make it uniquely suited to Bayview. The red balloons are inspired by the words of a 96-year-old community activist who said that the neighborhood was like a "balloon waiting to inflate and rise." The cows reference the historic Butchertown, once located at the site of the silo. Other patterns include shorebirds rising from the waters of the bay and a heron that references Heron's Head Park, a nearby environmental restoration project.

Ultimately, the mural helps define the neighborhood, even for people who don't live nearby. I've seen the Bayview Rise countless times while driving up and down the freeway a few miles way -- you can't miss it. For years it piqued my interest, and it likely does the same for the huge number of commuters driving on I-280 through San Francisco.

The Bay Lights by Leo Villareal / Illuminate

As engaging as all 27 exhibits featured on San Francisco's light art tour are, nothing comes close to The Bay Lights project, both for the sheer scope of the art itself as well as the logistical challenges needed to make it a reality. In true San Francisco fashion, artist Leo Villareal said the project "was built in the spirit of a startup and not accepting no for an answer."

Davis' elevator pitch to the many city and state agencies that needed to work together was simple: "I have an idea that might let your bridge outshine the Golden Gate for a little while." But when Villareal put together a one-minute video mock-up showing his vision for The Bay Lights, it got even easier to get the help the team needed. "[The video] transformed everyone's opinion about the project," Davis recalls. "The reality is, once you can visualize something, it changes the entire conversation. If you can get to the essence and the heart of it in 60 seconds, you suddenly have this very powerful tool."

The project was the result of two-and-a-half-years of collaboration between Villareal, Davis and a host of other contributors, particularly from a technical standpoint. Both Villareal and Davis say they're not terribly technical people, but they were facing a serious challenge. "We know how to make pixels into a screen, but to take those pixels and spread them out over 1.8 miles, 500 feet in the sky above water and live traffic -- it's an unusual challenge," Davis says.

Incredibly, the artwork has been built and attached to the bridge not once, but twice. The original Bay Lights were turned on in March 2013, and were shut down two years later by design. However, the area had such a strong response to the project and its closure that Davis and Villareal went back to work, seeing how they could make it a permanent installation.

To do that, Davis' nonprofit Illuminate organization persuaded the city of San Francisco and the California department of transportation (Caltran) to take over operation of Bay Lights. Illuminate raised the money to reinstall the lights, but then the group gave the artwork to Caltran, San Francisco and the state of California. Davis recalls his pitch like this: "We'll bring this artwork live, in conjunction with Super Bowl 50 when the eyes of the world are on the Bay area and on your bridge, and at that moment we gift the installation to you in exchange for your stewardship."

From a cost perspective, Davis said the maintenance comes to about $250,000 a year. With an operating budget of $8 million for the west span of the bridge, about 143 toll-paying cars a day cover the costs needed for upkeep. And when the installation went up the second time, the equipment needed was re-engineered to survive in what Villareal called "the bay's harsh marine environment."

With the installation now built to stand the test of time and the state in charge of its upkeep, The Bay Lights gives the bridge a shot to become as iconic as the Golden Gate. A big part of that comes from the artwork's simplicity, something Davis and Villareal had to fight to preserve when they were raising money. "There are ways of engaging in commercial stuff, but it's important to keep it pure," says Villareal. "The Bay Lights isn't aggressive. It doesn't demand your attention."

Indeed, any kind of visible commercial endorsement -- or anything beyond the abstract patterns you can see on the bridge every night -- would have kept The Bay Lights from becoming the kind of icon Davis and Villareal hoped for. "The piece became really accessible because it was free from the distraction of interaction," Davis says. "Would the heavens be any more majestic if you could rearrange the stars with your iPad? Fucking no."

"There are lots of illuminated bridges -- you can search Google and find 100 garish examples," Villareal says, "but there's something about The Bay Lights that's restrained." That tasteful restraint is now a hallmark of both of San Francisco's bridges. The Golden Gate has its copper color and breathtaking views, while the Bay Bridge has its lights. There's no doubt it's a better legacy than traffic jams.