We use QMessageBox to ask the user if they are sure they want to proceed with various destructive actions. It would be nice if we could include a checkbox in such dialogs with a "Don't show again" label. Thus if the user gets annoyed answering the common question they can simply check the checkbox and never be bothered again.

You can actually do this already by being able to pass any QAbstactButton to the addButton method, and are able to position it correctly through methods specified here:

http://blog.beef.de/2008/01/12/qmessagebox-widgets/

But it would be nice to have this be a lot easier in the QMessageBox class.