When I was a kid I used to do this to the computers at Costco, writing a similar script in Batch and inserting it into demo computers' autoexec.bat. It was like four lines and I'd live-code it right in the store. (Mondo bonus points if I was able to do it on the machine with the cloned screens). It was fun to see which adults knew the CTRL+BREAK trick... very few did :P

Also, Mac OS has had text-to-speech since forever... it would even cuss for you. So why not open TextEdit and unleash a string of obscenities after about a paragraph of commas and periods? Don't forget to turn the volume all the way up!

Never got me arrested... did get me banned from the school computer network on multiple occasions though...