Pogoseat - Pioneers of the in-event seat upgrade technology and Text-to-Buy mobile ticketing soltutions.

Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.

Eventzilla - Eventzilla lets you sell tickets online and manage attendees from one integrated application.

Event Hunt - Startups and Tech Events Curated By Locals

Guestlist - Market events online, accepting registrations & ticket sales

Eventbrite - Discover Great Events or Create Your Own & Sell Tickets