The Bean

Is this an optical illusion? Nope. It's the underside of "The Bean," otherwise known as the Cloud Gate sculpture in Millenium Park. I think I'm in there about a million times. Look for me, I'm wearing a red jacket. :-)
Here's another view of it. It's impossible to shoot this without people in it. Maybe if you get out at dawn but we didn't want to get up that early when our children were at home waking their daddies up early and not us.