Looking up and down while spinning left and right

I have had this “Trippy spinning optical illusion” (found at the always interesting kottke.org open in a browser window since I found it on Feb. 1, 2016. From kottke.org: Somehow, this woman seems to be spinning both clockwise and counter-clockwise simultaneously. This is worse than the spinning ballerina. Anyone know who did this? Randomly found it […]