ExtremeTech has published a free excerpt from the book “Hacking Mac OS X Tiger: Serious Hacks, Mods and Customizations,” by Scott Knaster (US$16.49). “In this feature, we show you how you can hack Apple’s latest OS using TinkerTool, bring the world of Unix file ownership and permissions to the Mac, monitor memory settings, and do lots more,” notes the site. Thanks to MacMinute reader Michael Muchmore for this news tip. .