Sometime last week, spontaneous pieces of outdated playground equipment started appearing in the Lower Haight, spreading some holiday mirth and merriment through the neighborhood. According to neighborhood watchers, the rope-and-wood swings were first spotted at a few different locations along Steiner Street, each hand-painted with the cryptic, yet ever-so-playful word, "Unless".

While the locals at neighborhood blog Haighteration have yet to definitively pin down the man behind the pop-up playgrounds, clues point to artist Jeff Waldman. Last year, Waldman put together a similar project around town designed to get us zombie-like San Franciscans to connect with our inner children through moments of unexpected joy. After the San Francisco project, Waldman headed off on a globetrotting tour to hang swings in Los Angeles and Panama. Waldman and company are currently raising money to bring the project to La Paz, Bolivia and create a documentary in the process.

If anyone gets a ride on the swings before some nefarious DPW worker slices them down, do let us know how you enjoyed it. (Did your feet drag on the ground? Can you swing high enough to jump in to oncoming traffic? Was the velocity sufficiently exhilarating? All important questions.) In the meantime, we can think of at least one San Franciscan who is not a fan.