Here is my blog/phlog/gemlog. I use it for saving interesting things, thoughts and as a personal diary. I am rather harsh and rude person, so some posts could be unpleasant for reading, be warned!
It could be cloned as a Git repository (from here and here). Also it has Atom feeds.
You can post comments for any entry by sending plain text email (either text/plain or multipart/signed+text/plain, UTF-8/US-ASCII/ISO-8859-1 charsets) to special email address specified in each entry (commit's hash). For example by using:
$ mutt "mailto:email@example.com?subject=414f5c87bc611b9b79c8ff3cca02736d703e949f" <<EOF my example comment's text EOF