I always forget the Safari has a Debug mode for when you are developing web apps which allows the logging of JavaScript errors. To display the debug menu in Mac OS X, open the Terminal and type:
defaults write com.apple.Safari IncludeDebugMenu 1
To display the debug menu in Safari 3.0 for Windows, use a text editor to add the following to the Preferences.plist file located at C:\Documents and Settings\USERNAME\Application Data\Apple Computer\Safari\Preferences.plist :