Diner en Blanc, the flash mob-esque dinner party that sent thousands en masse, white-garbed and hungry, scrambling through the streets of Philly last year in search of the guerrilla picnic’s secret location, is coming back for round deux this summer. The date hasn’t been announced yet, but the waiting list just opened up. If you want in on the spectacle, you have to sign up and await further instructions to be emailed to you. And you better do it soon. Just 1,300 of the 4,000 who signed up for last year’s diner were selected to participate in the fete.