Eventbrite - Discover Great Events or Create Your Own & Sell Tickets
Mixily - Hosting your event just got easier.
pretix - pretix helps you to sell tickets for your event in an easy way. It supports multi-lingual events and provides a wide range of features
EvePlaner - EvePlaner.net lets you create and manage your events the easiest way possible.
Ticket Tribe - Sell tickets online with no fees per ticket
Tiny Reminder - Collect content & files from busy clients