Some of us like mystery of graffiti. It’s such a public art but we rarely know anything about the people that create them. And although we think that not all of them are worthy of a photo, we’re still curious to check out the newly released San Francisco Street Art by Steve Rotman. Just a few months ago, Rotman published Bay Area Graffiti. The author will present his book at Books Inc. on May 11. In the meantime, you can read an interview with him at Fecalface.com. And if anyone knows Ribity, the person behind the frog you spot everywhere around town, we’d love to meet him.

If you’re not sure what to do tonight, Galeria de la Raza is having an opening party for Exit Art that looks interesting. The exhibit includes “Jumping the Fences,”  a series of performance-based photos by Papo Colo, and “Renegades,” a series of videos documenting 25 years of performances produced by or presented at New York’s Exit Art.

And on the job market front, SFGate reports that California’s unemployment rate rose to 11.2 percent in March, which means that 2.1 million Californians are out of work. It’s the highest since before World War II.

Today is the anniversary of the 1906 earthquake. Happy 105th anniversary golden fire hydrant! Thanks for saving the neighborhood.