Lappy took a spill. Screen broke.
OK, it's not the end of the world. In fact, the lappy is still entirely functional save a smattering of dead pixels that are hideous to look at but don't actually render the screen unusable. And a replacement screen is hardly going to break the bank; these things apparently come pretty cheap. Although it's a Macbook, it's not one of the horrible "unibody" machines that are virtually impossible to repair so swapping the screen will only take about an hour, a few odd screwdrivers, and a heaping helping of profanity because those tiny screws are annoying.
Maybe I'll find another laptop for free in a bin. I've been having surprising luck with that.