Posting this feature / plugin idea in hopes that it already exists somewhere.
The feature would allow a user to import the complete contents of a web page to a new topic using a URL. The real value of the feature would be in stripping out all HTML tags, converting formatting into markdown, importing image assets, and converting onebox-able content into simple links.
I suspect that a lot of that magic code has already been implemented for migrations from other forums. So this feature/plugin could be feasible to implement leveraging existing migration packages.