Time Machine will standard use all the available disk space on an external drive or a external server volume. You can setup a limit how much disk space Time Machine may use. Use this defaults write Terminal command:
Stop Safari creating favicon caches
Safari stores favicons in a database named ‘WebpageIcons.db’ located in the folder: ~/Library/Safari/Icons. It is possible to disable the creation of this database with the following command:
Mission Control: Fullsize window previews
In OS X Lion the thumbnail previews of windows from the same app are grouped together. By hovering the mouse over these thumbnails and scrolling up, you can expand the group of windows. It is possible to display these windows in full size.
Activate element inspector in the Mac App store
In the Mac App Store is a hidden element inspector available that lets you view the source of any page or element. It is possible to extract text or images, and adding your own code through the console option.
Enable momentum scrolling for Magic Mouse
The Mouse System Preferences pane does not include an option to enable momentum scrolling. The setting is a hidden preference. Use following command in Terminal to enable momentum scrolling.
Enable spring loaded Dock items
Spring-loaded Dock items are supposed to save you time by allowing you to drag a file over the folder/icon. Hover it for a few seconds and the application/folder will open. Use the following command to enable these feature:
Enable the full size window preview in Mission Control
Mission Control groups previews of windows from the same app. By hovering the cursor over a these group and scrolling up, you can see that the group showing more detail in those behind the main window. With the following command you enable to see a full size preview of the contents.