<A target="_blank" href="http://www.pcworld.com/article/166327/5_things_you_should_know_about_snow_leopard.html?tk=rss_main">Users of Leopard, OS X 10.5</A>, can upgrade to Snow Leopard for $29. The new OS is faster and requires less disk space. It won't run on the older PowerPCs. It will be available in September.