Argh!!… Your web application has to sort a lot of data and you get the dreaded error message… “A script on this page may be busy, or it may have stopped responding…” Or maybe you’re writing some image processing code that takes forever on large images… Your UI is non-responsive. What are you going to do!!?… You could try to break up the work into small pieces and use timers to spread out the work. But what a PITA!