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Members is a plugin that extends your control over your blog.
WP-Members™ is a plugin to make your WordPress® blog a membership driven site.
Now with shortcodes and post/custom-post-type support, as well as a comprehensive admin interface for setting plugin defaults
Events Manager is a full-featured event registration plugin for WordPress based on the principles of flexibility, reliability and powerful features!
Typekit offer a service that allows you to select from a range of hundreds of high quality fonts for your WordPress website. The fonts are applied using the font-face standard, so they are standards compliant, fully licensed and accessible.