Reddit API seeks to integrate the reddit.com API functionality with your Drupal website. Currently in the early alpha stages of development, it provides the following:

The ability to send messages to a reddit user's inbox

Mapping between user accounts on your site and reddit.com with a verification process allowing users to confirm the linkage by responding to a message sent to their reddit inbox.

Local storage of a single subreddit's flair and ability to use that subreddit's flair with your users that have linked their account to a reddit account

Cron based synchronization of the local flair cache

Soon to be added for first alpha:

Ability to Mass Message a selected role via Reddit Inbox

Automatic submission of content upon publishing

a Flairbot that can provide your users the ability to manage/modify their flair from within your site

Ability to add comments from your site to reddit (similar to twitterbot, mirrorbot, etc)

I am actively seeking co-maintainers, and will be uploading the first alpha release by Jan 1, 2012.