Excellent plugin -- it really should be worked into the WordPress core, say I.
However, when it comes to restricting access to a certain post/page/custom_post_type, it would be a delight to not only grant permission to specific roles, but also individual users, regardless of which role they are a member of.
The work around is currently to create a unique role for each user, but it would be oh so more elegant if there was the ability to connect/restrict posts-to-users, simular to how scribu's excellent posts-to-posts plugin handles this type of many to many relationship.
Any thoughts?