Submit Once - preventing duplicate nodes (and even comments)

I'm surprised that there are no hard and fast solutions to prevent duplicate submissions of content, accidental or otherwise. Leave spammers & spoilers aside for a moment, there are people, my mother & wife included, who will hit the submit button again because they're not getting an instant return.

I've found discussions here & there on the subject and I've seen several non-Drupal solutions (that don't seem to work on Drupal) but there is no conclusion, no solution that solves this issue and solves it without side-effects.

I'm sorry to say I cannot provide the answer here - I'm just bringing it up because I think it should be a fundamental inclusion in Drupal. I'm bringing it up to see if anybody else has something to say, offer or suggest.

Is there really no way to disable the submit button, even lockout the whole page, once a node has been submitted???