The Cellar IOTD is very worthy of a bookmark or two.
"'Sunday Afternoon on the Island of La Grande Jatte' is the English name of it, and surely you've seen it; it's the prime example of pointilism, the technique Seurat came up with. You know, where the image is created by thousands and thousands of tiny dots. The technique copied in most types of photo reproduction and laser and dot-matrix printing.
If nowhere else, you've seen it studied by Cameron in 'Ferris Beuller's Day Off', since it lives in the Arts Institute in Chicago, Chicago being the city in which Beuller took his day."