The FAQ says: [Comments are temporary "Post-It" notes left on a question or answer](https://meta.stackoverflow.com/help/privileges/comment), meaning that [we should not expect them to be around forever](https://meta.stackexchange.com/questions/19756/how-do-comments-work).

So I would like to backup all my comments on a regular basis: what is the easiest way for me to download all my comments across all Stack Exchange sites?