Virus-Free Macs  #147;The single most effective way to avoid viruses and spyware is to simply chuck Windows altogether and buy an Apple Macintosh, #148; writes Walt Mossberg in the Wall Street Journal.  #147;There has never been a successful virus written for Mac OS X, and there is almost no spyware that targets the Mac. Plus, the Mac is invulnerable to viruses and spyware written for Windows. Not only is it more secure, but the Mac operating system is more capable, more modern and more attractive than Windows XP, and just as stable. #148; Sep 17