Yoast - Yoast offers plugins to improve SEO and optimize web sites and blogs.
Tribe.so - Tribe is a white-label platform, empowering the new generation of online communities.
Jackmail - A newsletter plugin for Wordpress.
Higher Logic - Private, secure online communities that stimulate conversation and ignite engagement.
Wordfence - Comprehensive security plugin for WordPress.
Trello - Infinitely flexible. Incredibly easy to use. Great mobile apps. It's free. Trello keeps track of everything, from the big picture to the minute details.