1.)Dealing with important files? Try giving FileVault a try. It automatically encrypts and decrypts your files on the fly when you use them. Head into System Preferences -> Security -> FileVault to activate it.

2.)Got a laptop? Wanna know a little more about your battery life? Go to: Apple Menu -> About this Mac, then click on more info. This will bring up the System Profiler. Then select Hardware from the list on the left, then choose the power sub menu. Once there, scroll to the bottom to view detailed results. You will be able to see such things as Cycle count(number of times charged and discharged) Battery health,Manufacturer, and Voltage.

3.) Having some problems with your mac? Try zapping your P-Ram, you would be surprised what it can do. apple-option-p-r on start up.