GnuCash - A personal and small-business financial-accounting software, licensed under GNU/GPL and available for Linux, Windows, Mac OS X, BSD, and Solaris.
ERPNext - The ERP Software that helps you take full control of your business. ERPNext is both powerful and easy to use.
Xero - Xero is online accounting for your small business.
Odoo - An all-integrated business app suite to unleash your growth potential.
CheckStream - CheckStream check printing software
OCTO ERP - All-in-one platform to track and manage everything about your business. It's an ERP, CRM, and BMS combined at an affordable rate for businesses of any size. RFID, barcode, GPS, NFC and IoT built-in functionalities out-of-the-box.