rsstodolist av Aurélien Thieriot, Grégory Paul

That extension make rsstodolist more convenient to use.

By a single click, you can add the URL of the webpage you're viewing to an RSS feed.

Typical example is marking web pages to read later.
Also, you may also "push" links to another RSS feed that you give to a friend. That's another cool use case.

Check rsstodolist.eu for further details or check source code.