For real lulz: print this pattern of small yellow dots on all your business correspondence with big companies, just to screw with their document management systems. Hours of endless fun for all the bureaucrats!
(There's got to be a PDF/postscript file/print filter for the pattern somewhere. Anyone? EDIT: Ah, found it here: http://wildsparx.com/eurionize/ -- download has vanished, but source is on github: https://github.com/jplona/code/blob/master/eurionize.pl )