Fun story about this: in college we had to make a barcode reader out of a simple phototransistor. To scan the barcode, you had to slide the device along a piece

Fun story about this: in college we had to make a barcode reader out of a simple phototransistor. To scan the barcode, you had to slide the device along a piece of paper. The barcode scanner had to be isolated from ambient light so that we'd get a good reading. However, our project was to read a lot of information via the barcode (a paragraph of English text encoded as Code 39 or similar, can't remember the exact details), so it wouldn't fit on one line of paper. Lots of teams decided to implement complex heuristics to determine when to ignore readings when lifting the barcode reader off of the page and to scan the next line. But we decided to use boustrophedon to generate the page with the barcodes on it so that we never had to lift the barcode scanner off of the page. You just had to scan left to right, then down one line, and then right to left.