Embeds media in FriendFeed comments through oEmbed to make it more like an imageboard (or better, a mediaboard since it embeds also videos). Flickr, Vimeo and Youtube are the most popular embeddables supported but there many others.
The image-embedding part can be potentially annoying for content hosts, since it's obviously hotlinking their images. Contact me if you feel that it's really unfair. I decided to go for it because the script is very un-popular :)
For bugs, feel free to file a bug or to fork and send me a pull request on github.
Tested in Google Chrome on Ubuntu (Linux). Can be installed in Google Chrome / Chromium directly. Needs Greasemonkey extension to work in Firefox (if it works at all, I haven't tried it; let me know or just fork and edit this statements if you do :D).