System Scheduler - System Scheduler for Windows, Free Task Scheduler Software replace Microsoft Windows Task Scheduler
Attendize Event Ticketing - Attendize is a free & open-source ticket selling and event management platform
VisualCron - VisualCron is an automation, integration and task scheduling tool for Windows.
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets
Freebyte Task Scheduler - Freebyte Task Scheduler, freeware for Windows and Linux/Wine.
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