I'm a frequent reader of Reddit's Cooking subreddit. Users have some amount of anonymity because usernames aren't attached to real identities; however, the usernames create pseudonymity. Judith Donath wrote a lot about how pseudonymity can help create more civil discourse in online discussions—people are able to honestly state their minds under their usernames, while still being held accountable for their words through artificial indicators of reputation, i.e. Reddit karma and visible post history. The subreddit also allows moderators to give flairs to users, so reliable and frequent users can receive flairs that lend credibility to their posts, i.e. well-known or famous chefs who participate in discussions.