I live on the top floor of a loop high rise. I've seen that 4 or 5 times in the last 15 years. Never heard it sloshing, though. This morning, a finally balanced lid on some kitchen equipment was chattering away. Only once have I had to go lay down, but that really doesn't stop the swaying either - a strange feeling in your own house.
Einstein was a genius because he realized scientifically that its all relative. http://www.forbes.com/2003/11/19/cx_np_1119feat.html
Funny, my dream is to move to a place where I can have lots of horses and lots of dogs. That does not include downtown anywhere. I have lived in chicago for 30 years and for part of that I have lived on high rises, and I have no idea about all this windy city stuff about buildings swinging in the wind is about. Ok, the Sears tower, yeah, but your run of the mill sixty footer? Nah.