What other apps have secret debug menus?
Reminders

defaults write com.apple.reminders RemindersDebugMenu -bool true

Disk Utility

defaults write com.apple.DiskUtility DUDebugMenuEnabled -bool true

App Store

defaults write com.apple.appstore ShowDebugMenu -bool true

Safari (not to be confused with Develop menu which can be enabled in Preferences)

defaults write com.apple.Safari IncludeInternalDebugMenu 1



iCal

defaults write com.apple.iCal IncludeDebugMenu -bool true

Contacts

defaults write com.apple.Contacts ABShowDebugMenu -bool YES