OpenPapyrus - The enterprise management system OpenPapyrus
EspoCRM - EspoCRM is open source CRM (Customer Relationship Management) software that allows you to see, enter and evaluate all your company relationships regardless of the type.
Snipe-IT - Managing assets with a Google doc or a shared Excel spreadsheet is more common than you think.
CiviCRM - A Constituent relationship management for the Civic Sector
ERPNext - The ERP Software that helps you take full control of your business. ERPNext is both powerful and easy to use.
Less Annoying CRM - A simple customer relationship manager made just for small businesses. Manage contact info, track leads, and never miss a follow-up.