If you want to go beyond System Preferences and change other settings on your Mac, you can do so with the Terminal window. But TinkerTool makes it even easier by giving you a list of potential settings and a user interface to make the changes without typing.
While today's Macs have a recovery disk partition on the internal hard drive that makes it easy to recover from problems, it can also be useful to have an external recovery disk. It is very easy to create one using Apple's Recovery Disk Assistant for Lion and Mountain Lion. it could come in handy if your hard drive is damaged or you need to swap it out for a new one.
Save dialogs in Mountain Lion have two different modes: compact and expanded. Learn how to easily switch between them. The last setting is remembered, but you can also set a default using the Terminal. Also learn how to switch between saving to iCloud and saving to your local hard drive. You also have two modes in the Print dialog.