Safari Debug Menu: Changing User Agent, Debugging JavaScript

I usually don't use Safari, but here's a great item to note if you need to use it. You can enable development tools through a preference setting. Simply open up a terminal window and execute the following:

defaults write com.apple.safari IncludeDebugMenu 1

This will enable a new menu in Safari containing controls to change the user agent, disable various functions like javascript or caching, and/or start javascript debugging.