Thumb It – Plugin plus…

Here’s what I’d like to make easier for myself. I’m browsing, and I see a page I’d like to blog about. (Sounds like I should just Press It, but read on.) The post to my blog will include a thumbnail of one of the images on the target page.

Here’s what I’d like to do. I’d like to “Thumb It.” That would upload to my WP host a thumbnail of the image in question, and only a thumbnail. It would open a Write window, similar to Press It. But the post would have a img tag, with src=newthumbnail, which would be wrapped in a link to the target page.

Ideally, Thumb It would be, not only a plugin for WP, but also an addon for Firefox. That way, I could just right-click on the target image, and I’d be much of the way to a post with a thumbnail.

How close can I get to this, using available plugins, etc.? I have looked at a few existing plugins, but none of them seem to get me very close to this. Sorry if I’m missing something. Thanks for any help you can offer.
Andrew