Confession: I wrote a couple of these when I was a teenager, including one that would give you a crazy color scheme and print 'Your PC is on an acid trip' as a

Confession: I wrote a couple of these when I was a teenager, including one that would give you a crazy color scheme and print 'Your PC is on an acid trip' as a DOS error. I put one on a high school PC once and it ended up actually spreading around. They were pranks and weren't designed to really hurt anything, though I'm sure they could be annoying. It's how I learned assembly language and C actually.