Mac OS X – How to Get Combined Size of Multiple Files

1. Select file (hold down command for multiple selection)
2. Hit Command + Option + I

With Multiple Item Info dialog box open, you can select other file(s), and the information will be updated on the fly

Mac OS X – How to Hide Every Window

1. Hold down Option + Command and click on the blank spot on the desktop

This will hide all open windows except Finder

To hide all open Windows, apart from the one you are working on hit Option + Command + H

Mac OS X – How to Create a List of File Names

1. Open Finder
2. Highlight the file(s) that you want to copy
3. Press Command + C
4. Open Text Editor (such as TextEdit, Ms. Word, Ms. Excel, Ms. Outlook, etc)
5. Press Command + V

Mac OS X – How to Hide Desktop

1. Open Terminal (Finder > Applications > Utilities > Terminal)
2. Enter script as below:
defaults write com.apple.finder CreateDesktop -bool FALSE;killall Finder

To Restore Back Desktop, enter below script
defaults delete com.apple.finder CreateDesktop;killall Finder