I'm done with this. If someone wants to maintain it send me a note and I'll transfer the repo. Or just fork it, or whatever.

GNU social plugin that adds an icon to each notice.
Clicking the icon allows visitors to get the necessary HTML to embed a notice on a webpage.

The extra icons on the timeline:

The dialog with the HTML code to copy/paste:

1. Navigate to your /local/plugins directory (create it if it doesn't exist)
2. git clone https://github.com/chimo/gs-embedNotice.git EmbedNotice
3. Tell /config.php to use it with: addPlugin('EmbedNotice');

The embed icon should appear in each notice.