Wiggles and Giggles! Shhh! Indianapolis

I was across the street. I looked over. It started giggling, and then wiggling. And it didn't stop. So I took a picture. So you would believe me. The sturdy sign. Erect and unmoving. The neatly lined glass doing its best to keep everyone in line. And yet. It wiggles. Maybe they were my giggles.