I'm importing hundreds of thousands of forum posts into my bbPress install. Many of the threads have images in them linked from the old site or from other sites around the web.
Not to long ago I found a plugin that would scan all of your posts for 'linked images' and it would go and download the images, save them to the media folder and properly attach them to the post locally.
I can't find the plugin, and I am hoping someone remembers what I am talking about.
ring any bells anyone?