LJ has a feed for the latest images posted publicly here:
Someone has set up a community to scrape off any image that is posted that meets LJ icon requirements and post them to a community.
Now, the part that's the most annoying is that the images are hotlinked from the image source.
You can opt out of your posts being included in the latest feed by going to the Admin Console and type in these commands:
set latest_optout yes
set for "community name" latest_optout yes
The community mentioned above is iconscraper.