I've had two incidents in the past few days where I moved forward and back in my browser to check some info, then edited my post. Unfortunately I edited the original posting form rather than the edit form, and made duplicate posts. Now I know I have only myself to blame for this, but I thought I would recommend a fix we did at one place I worked:
Every time a node-creating form was loaded (or in our case, anything that would cost money), the form carried a hidden field with a value set at the load time. When the form was processed, this field was checked against a list of recently used values. If it matched, it meant that the form had already been posted, and the user was bounced to a preview screen and warned. If it didn't match, the form was posted, and the number was marked as "used" for a period of time. This doesn't stop EVERY occurance (one could come back to the browser after the expiration time and resubmit the form), but it helps.

In reply to Duplicate posts by swiftone

Title:
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