MAIL:
clean mail index: cd ~/Library/Mail; sqlite3 Envelope\ Index; vacuum << ^D

SPOTLIGHT/DASHBOARD:
rebuld spotlight: sudo mdutil -E -i on /
deactivate dashboard: defaults write com.apple.dashboard mcx-disabled -boolean YES
disable spotlight: sudo chmod 0 /System/Library/CoreServices/Spotlight.app

SYSTEM:
clear caches: sudo rm -rf /System/Library/Caches/* /Library/Caches/* /Users/pwall/Library/Caches/*
clear logs: sudo rm -rf /Users/pwall/Library/Logs/* /Library/Logs/* /private/var/log/*
software update: softwareupdate -ia
restart net device: sudo ifconfig en0 down; sudo ifconfig en0 up
Force eject: disktool -e disk#
ipforwarding: sudo sysctl -w net.inet.ip.fw.enable=1
rebuild launch services: /System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/LaunchServices.framework/Versions/A/Support/lsregister -kill -r -domain local -domain system -domain user
maintenance scripts: sudo periodic daily weekly monthly
check prefernces: sudo find /Library/Preferences -name "*.plist" -print0 | xargs -0 /usr/bin/plutil -lint -s; find /Users/*/Library/Preferences -name "*.plist" -print0 | xargs -0 /usr/bin/plutil -lint -s
reset font cache(restart after): sudo rm -rf /private/var/folders/*/*/-Caches-/com.apple.ATS
update locate: /usr/libexec/locate.updatedb