"TinkerTool System is a professional all-in-one maintenance tool for the Macintosh platform. It allows you to change advanced operating system settings and offers a wide variety of maintenance features. It strictly complies with the software guidelines for Mac OS X, and also uses Apple's official instructions and recommendations for the resolution of certain system problems.
"TinkerTool System is very different from other maintenance applications because it never uses any scripts and is fully integrated into the security architecture of Mac OS X. . . ." [from developer's website]