Does anyone know how to disable unicode text input in text fields?
Some applications and text views just don't support DefaultKeyBinding.dict.

If you create a new keylayout with Ukelele, you can for example make ⌥A insert nothing instead of å. Or you can reassign key combinations that enter dead key states (like ⌥U on the U.S. layout) so that they can be in used in DefaultKeyBinding.dict.


Keyboard layouts in ~/Library/Keyboard Layouts/ can't be selected in password dialogs or the login screen, but ones in /Library/Keyboard Layouts/ can.
XML keylayout files don't work with the popovers shown when holding keys, but keylayout bundles do.
To apply changes to a keylayout, you currently have to for example run sudo touch /Library/Keyboard\ Layouts/ and log out and back in.
The default input sources can be removed by editing ~/Library/Preferences/ByHost/com.apple.HIToolbox.*.plist.


KeyRemap4MacBook can for example change ⌥B to ⌥← in all applications except iTerm and Emacs. See this question.