• Show hidden files and folders in Finder
• Show hidden files and folders from an application’s Open dialog
• Remove Duplicate Entries in ‘Open With’ Menu
• Show your workings with Calculator

Show hidden files and folders in Finder

From a terminal window

$ defaults write com.apple.Finder AppleShowAllFiles YES

Then relaunch Finder with Option () + Right Click, Relaunch. Switch back using NO.

Show hidden files and folders from an application’s Open dialog

When you’ve got the dialog open, just hit Command () + Shift () + . to toggle. Nice.

Remove Duplicate Entries in ‘Open With’ Menu

Remove duplicate entries from the terminal window.

$ /System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/LaunchServices.framework/Versions/A/Support/lsregister -kill -r -domain local -domain user

Show your Workings with Calculator

Hitting Command () + T in the Calculator app shows the paper tape so you can see you past calculations!