There are uses for this besides ads. When I worked on Google Reader, something like this would have been incredibly useful. At the time, the only truly safe wa

There are uses for this besides ads. When I worked on Google Reader, something like this would have been incredibly useful. At the time, the only truly safe way to handle embed/object/iframe in post content was to completely filter it out. That's pretty terrible for usability, though. We ended up having a exceptions in our HTML sanitizer embeds of content from certain sites (eg: elves of popular video sites like YouTube and Vimeo were allowed). I always hated that solution because it made us vulnerable to any site in the whitelist (whether because they become malicious, or because they themselves have a vulnerability), it was unfair to smaller/newer sites, and it was a additional maintenance burden.