Maker Swipe File - 100+ high-performing Tweets to help you grow your audience
Calendify - Calendify is an event community where you can share, publish, and subscribe to event calendars. It helps you to stay informed about what you are interested in and what is yet to come.
Toolset.com - The complete and reliable plugin for managing content types in WordPress.
Upcoming.org - A simple way to share and discover interesting events
TweetPilot - Grow a relevant & responsive following on Twitter
Colloq.io - Discover a new way to the conferences you like.