I know of a few blogs people are running on Drupal 8. Having just had trouble setting up mine, I thought it would be helpful to get a list of more sites that are live and in the wild on d8. When I could find posts about the why or how of launching a d8 site, I included it in parenthesis.
WIP Please tweet @YesCT to add your d8 site to this list. If you have a post about why you started a d8 site, or details about the server/hosting setup, let me know that too.
We can sometimes check if a site is Drupal 8 by looking for core/CHANGELOG.txt
Adventerous people running personal blogs on Drupal 8:
@cwork_chris @opdavies http://running-on-drupal8.co.uk/
I think usually those are running a snapshot of Drupal 8, at a certain commit. I do not think that these people chase head.
Bigger projects trying out Drupal 8: