Marcel Bresink has released TinkerTool 4.95, a small update to his under-the-hood customization system utility. The app now offers a setting that enables the debug menu of Disk Utility and the App Store application in Mac OS X 10.7 Lion or later. For 10.8 Mountain Lion users, the release adds settings to control smoothing and to disable the default behavior of asking if you want to save new documents to iCloud in supported apps (such as iWork, TextEdit, and Preview). It also adds a pane to control Resume behavior for individual applications in Mountain Lion. (Free, 3.9 MB, release notes)
Turn Off Filename Extension Warning
In Leopard, Apple fixed an annoying aspect of working with the Finder in Tiger. Previously, if you changed a file's extension, the Finder prompted for confirmation. But since no one has ever accidentally changed a filename extension, Apple thankfully added an option to turn that warning off in the Leopard Finder's preferences. Choose Finder > Preferences, and in the Advanced screen, deselect Show Warning Before Changing an Extension.