Sorry to put this bluntly, but why are you even using sudo/Terminal to begin with? Based on what you've posted so far it's clear you really have very little idea of what you're doing.
Well I may not be a programmer or a hacker or someone who spent 5 years in college getting a degree in computer programming, but what I do know how to do is read.
Like
$ cd /System/Library/CoreServices/CoreTypes.bundle/Contents/Resources
$ sudo mv AliasBadgeIcon.icns AliasBadgeIcon_OFF.icns
removes alias arrows for icons
And
sudo pmset -g
sudo pmset -a sms 0
which disables sudden motion senson
And
sudo defaults write /Library/Preferences/com.apple.loginwindow LoginwindowText "Your Message"
To add a message to the login window
Or how about to change the frequency of Time Machine backups?
sudo defaults write /System/Library/LaunchDaemons/com.apple.backupd-auto StartInterval -int 1800
And since I never use spotlight maybe I should just remove the icon its kind annoying anyways
sudo chmod 0 /System/Library/CoreServices/Spotlight.app
killall Spotlight
want to make the menu bar completely transparent?
sudo defaults write /System/Library/LaunchDaemons/com.apple.WindowServer 'EnvironmentVariables' -dict 'CI_NO_BACKGROUND_IMAGE' 1
what about making it grey?
sudo defaults write /System/Library/LaunchDaemons/com.apple.WindowServer 'EnvironmentVariables' -dict 'CI_NO_BACKGROUND_IMAGE' 0
when you decide Apple got it right in the OS to change it back
sudo defaults delete /System/Library/LaunchDaemons/com.apple.WindowServer 'EnvironmentVariables
Oh and my personal favorite, when you tell someone they are wrong for wanting to learn something
sudo If you don't want to help with someones question please go to the next thread.
Sorry for the rant guys, but I am tired of people telling me not to do something instead of telling me why not to do it, then telling me how to do it and let me make my own decision whether it may be right or wrong.