Giving a presentation is hard enough without worrying about your computer breaking down in front of hundreds of onlookers. But whenever you use laptops and project your mouse-clicks onto a big screen, problems can erupt. Always re-boot your computer just before you begin. Turn the machine off, wait 20 seconds and turn it on again. This purges the computer’s memory and ensures you only open the desired application that you want for your public demonstration. Also pack your PC with lots of memory—at least 64MB and preferably 96MB. Lack of memory commonly causes computer lockup. Source: Presentations, June 1999.