TechEvents.co - Tech and startup events aggregator
Slack Events API - Subscribe to events in Slack via HTTP
Event Hunt - Startups and Tech Events Curated By Locals
B12 Bookings - Bookings scheduling software that integrates with your site
EventsApp - A simple concise app for creating and sharing events.
Guestboard - Lead powerfully-organized group events with Guestboard – a modular event platform that gives groups of 10-1000+ people a central space to coordinate, build excitement, and save money. No more crazy email threads. No more massive group texts.