There's a photo going viral right now that we thought we'd share with you, because it's got that perfect mix of WEIRD and CONFUSING. A girl in the Netherlands posted a photo earlier this week of her and her sister posing with some friends at a club . . . and her sister's arm looks about SIX FEET LONG. Now . . . it's all an optical illusion that's caused by the perfect positioning of the people, their clothes, and something that's either a purse or a furry coat. But as far as optical illusions go, this is a good one.