The City of Lights no more: Parkour aficionados are turning off commercial establishments’ “wasteful lights” in Paris, the New York Times writes. Videos (watch: runtime: 1:02) show ninja-like young men running, leaping, and putting their “physical abilities to good use” to reach elevated emergency light switches on storefronts. The nocturnal pastime began a couple years back and has gained momentum amid Europe’s energy crisis. Some call it trespassing — but others say the athletes are simply enforcing an often-ignored Paris law requiring stores to turn off their signs between 1am and 6am.