At university there was floating around a Postscript file which would render a Mandelbrot image at 300dpi.
There were emails from the IT department begging people not to print it on the elderly Laserjet IIIs during peak runs because it would take about 30-45 minutes to run, and the job couldn't be cancelled without physically power cycling the printer.
Back in the day (we're talking 80s) I wrote similar postscript (I remember also some sort of Douglas Hofstadter-esque strange attractor?). The argument for doing this was entirely practical: The Apple LaserWriter in the computer lab had a 68000 processor, which was a darn lot faster than anything else in the room, plus the only way to do high-dpi raster output.
There were emails from the IT department begging people not to print it on the elderly Laserjet IIIs during peak runs because it would take about 30-45 minutes to run, and the job couldn't be cancelled without physically power cycling the printer.