Sloan also has a package written by OF that sets up personal communities for Users in the dotLRN framework. I only had a chance to play with it briefly, and its never been used in production. Basically it sets up each user's community similarly to how classes and communities are set up and thus should allow you to mount dotLRN enabled packages for each User. Each User is then able to control access by adding other users as members or administrators.
Modifying lars-blogger as Lars discusses is probably a better solution for this specific problem. But personal communities may be a useful concept for someone out there so I wanted to mention that the code exists. However, please be aware that personal communities is in development state, and has never been deployed on a production system nor is it an official part of dotLRN.
