Member Access
Much as it may defy logic, restricting content behind a login is not as simple as classifying a page or post as “private”, this plugin allows for content to be classified as “public” based on site membership. Here is how the author describes it:
Member Access allows a WordPress administrator to make individual posts and pages accessible only to logged-in members. Member Access allows global configuration so that all posts or pages can be viewable by everyone (the default) or only by members, and it also allows each post and page to override the global setting.
Register Plus Redux
The core code of WordPress allows site registration to either be open or closed, which leaves a huge gap since open registration does not come with a moderation option. This plugin holds registration until such time as an administrator approves them — as well as several other useful options
Sidebar Login
Sidebar-Login has both a widget and a template tag to allow you to have a login form in the sidebar of your wordpress powered blog.
It lets users login, and then redirects them back to the page they logged in from rather than the backend, it also shows error messages.
