After adding support for OS X 10.9 Mavericks in its version 5.0 release, TinkerTool 5.1 from Marcel Bresink is now sandboxed for better security. The under-the-hood customization system utility also does away with the Login Items pane as it’s no longer useful for Mavericks, differentiates between the actual Lucida Grande typeface and the new screen system font introduced with OS X Mavericks, reinstates the preference setting that enables you to copy text displayed by Quick Look (for 10.9.1 and later), and reduces storage space used by the preference reset feature. While the latest version of TinkerTool requires 10.9 Mavericks, Bresink continues to offer older versions of TinkerTool for those running previous big cats, all the way back to 10.1 Puma. (Free, 3.9 MB, release notes)
Sleep (and Lock) Your Screen
When you are walking away from your computer, it's fairly common practice to start your screen saver and lock your screen. But did you know that there is a built-in keyboard shortcut in Mac OS X to sleep the screen?
Press Control-Shift-Eject and your monitor sleeps without engaging the screen saver.