Attendize Event Ticketing - Attendize is a free & open-source ticket selling and event management platform
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
Ticket Tailor - Ticket Tailor is an easy-to-use event ticketing platform that allows event organizers of all shapes and sizes to sell tickets online.
Ticket Tribe - Sell tickets online with no fees per ticket
TicketSource - Free, easy to use online ticketing for your events.
Ticketsetup - 360° Ticketing solution for event organizers and venues.