Downloaded more than 300,000 times, OpenEMM calls itself the "#1 open source application for e-mail marketing," and because it's been under development since 1999, it's also one of the oldest and most mature tools of its kind. The link above will connect you with the open source download, but commercial support, services, hosting and an SaaS version are available through project owner Agnitas. Operating System: Windows, Linux.
44. Open ERP
Open ERP provides CRM, purchasing, manufacturing, warehouse management, project management, accounting, human resources, marketing, invoicing, payroll and application building capabilities. It comes in three versions: community, enterprise or the OpenERP Online hosted solution. Operating System: Windows, Linux.
One of the most popular open source ERP solutions, Openbravo offers an intuitive interface, integrated data model and modular design for maximum agility and ROI. It's not available in an SaaS version, but the company does offer an appliance version that's ready to deploy on the Amazon Web Services cloud. Operating System: OS Independent.
46. xTuple PostBooks
Open source xTuple PostBooks offers an integrated accounting, ERP and CRM solution. The xTuple software also comes in numerous commercial editions, and it's also available in a cloud version deployed on Amazon's infrastructure. Operating System: Windows, Linux, OS X.
This highly adaptable ERP solution for large, multi-site companies offers the features multi-national companies need, including massive scalability. In addition to the open source version, it comes in professional and enterprise version that users can deploy on their own servers or in Amazon's cloud. Operating System: Windows, Linux, OS X.
Opentaps incorporates e-commerce, customer relationship management, warehouse and inventory management, supply chain management, financial management and business intelligence features. The company boasts that you can deploy the software in just minutes with its Amazon Machine Images (AMI) for the Amazon Elastic Computing Cloud (EC2). Operating System: Windows, Linux.
49. TNT Concept
Best for small to medium-sized enterprises or independent professionals, this software describes itself as a "tool for Management of Operational Effectiveness." It's not a substitute for accounting software, but a complementary piece of software that eliminates the need for the multiple spreadsheets that many small business owners and managers use to run their companies. It's also available on an SaaS basis. Operating System: OS Independent.
ERP5 combines ERP functionality with CRM, supply chain management, material requirements planning and product data management. It's also available in a paid enterprise version and both free and paid SaaS versions. Operating System: Linux.
51. Orange HRM
Claiming more than a million users, OrganeHRM considers itself "the world’s most popular Open Source Human Resource Management Software (HRMS)." It also comes in a "Live" SaaS version that takes just 15 minutes to set up. Operating System: Windows, Linux, OS X.
Similar to Orange, WaypointHR tracks personnel information, attendance and leave, contract details, discipline, performance reviews and more. It also comes in a hosted, on-demand version. Operating System: OS Independent.
53. Open Applicant
Rather than a complete HR management tool, this app is specifically designed to assist with the hiring process. Besides the open source version, the company also offers a hosted version and commercial support. Operating System: OS Independent.
Xen has become the industry standard open source hypervisor, and it's used by many public cloud computing services, including Amazon and Rackspace. It's operating system-neutral, lightweight, secure and offers good performance. Operating System: OS Independent.
Short for "Kernel-based Virtual Machine," KVM is owned by Red Hat and included in the main Linux kernel. Unlike Xen, it only runs on x86 systems. Operating System: Linux.
JStock allows investors to track stocks on 26 world stock markets. Features include alerts, charting, market chitchat and cloud storage. Operating System: Windows, Linux, OS X.
This Web-based app makes it easy to create PDF invoices for your small business and track them. You can install it on your own server and PC or use one of the third-party hosting providers listed on the site. Operating System: OS Independent.
Top features of this Web-based invoicing solution include client management, invoice generation and tracking, time tracking and management, and support for multiple languages and currencies. The company also offers paid support or a hosted solution in addition to the open source software. Operating System: OS Independent.
With Opsview, enterprises can monitor their cloud, physical and hybrid infrastructure all from a single tool. It comes in both a free community download or a paid enterprise version, with an optional mobile module and other services available. Operating System: Linux.