Fixing duplicate "Open with" entries in Mavericks

Terminal:

/System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/LaunchServices.framework/Versions/A/Support/lsregister -kill -r -domain local -domain user;killall Finder;echo "Open With has been rebuilt, Finder will relaunch"

As seen on http://www.tuaw.com/2013/03/25/how-to-spring-clean-open-with-duplicates/