Change Font Smoothing

To decrease the level of anti-aliasing, use

defaults -currentHost write -globalDomain AppleFontSmoothing -int 1

Level 0  = No anti-aliasing
Level 3  = Max anti-aliasing (Default)

Log out and log in for the change to take effect.

How to become a root in MAC OS X

From Terminal when logged in as an admin user -

dsenableroot to enable,
dsenableroot -d to disable

Add separator to Dock

- Add a spacer to the application (left) side of the dock:

defaults write com.apple.dock persistent-apps -array-add '{tile-data={}; tile-type="spacer-tile";}'

- Add a spacer to the other (right) side of the dock:

defaults write com.apple.dock persistent-others -array-add '{tile-data={}; tile-type="spacer-tile";}'

Then, use 'killall Dock' to restart the Dock.