WordPress › OpenID « WordPress Plugins
Allows WordPress to provide and consumer OpenIDs for authentication of users and comments.
Bookmarks
MailChimp for WordPress plugin
Memberful — Sell subscriptions online
Professional membership software used by the web's biggest creators. Works with your website. Integrates with Stripe, WordPress, and MailChimp. Try it for free.
SubToMe
A Universal follow app for the open web
WordPress Membership | Membership Site Software | Memberpress
Easy to use WordPress Membership Plugin. Powerful Membership Software seamlessly integrates with WordPress, Stripe, PayPal and Authorize.net.
WordPress › Markdown QuickTags « WordPress Plugins
Replace the WordPress HTML editor with a Markdown one. Auto-pairing, wrapping, preview/render, customizable editor fonts and more.
Gravity Forms for WordPress - Form Builder And Lead Data Management Plugin For WordPress
WordPress forms are easy with Gravity Forms, the most trusted WordPress form plugin. Gravity Forms makes building advanced WordPress forms a breeze!
Twitter Commenters - Comment Auth using Twitter - MT Hacks
Post Entries via an External Form - MT Hacks
WordPress › Twitter Widget Pro « WordPress Plugins
A widget that properly handles twitter feeds, including parsing @username, #hashtags, and URLs into links.
WordPress › TweetPress « WordPress Plugins
Use your WordPress blog to host the photos you post to Twitter!
Lithoglyph - Mondrianum