You can check out these two links. Near the end of the 1st post in the first link is a short piece about Advanced iFrames, and immediately below the posted image is about Advanced iFrames.
Near the end of the end of the 2nd topic (Onebox challenges) is something interesting you could try… a curl - and the post gives the code to use (just swap out your URL for the one shown).
Rich link previews with Onebox
Onebox challenges