Oh, look, it’s a standard, boring skyscraper that looks like all the others. Honestly, the real issue with the Standard Oil Building, now Aon Center, was back in 1974 when the geniuses decided to slap expensive marble along the sides of the building. Sure enough, the marble cracked and a big piece came off, falling on top of the building next to it. Needless to say, they had to do some renovations.