38. OpenERP
Replaces: NetSuite , Microsoft Dynamics
OpenERP includes modules for CRM, accounting, point of sale, project management, warehouse management, human resources, purchasing, manufacturing, marketing, invoicing and an application builder. The suite of apps is also available on an SaaS basis. Operating System: Windows, Linux, OS X.
39. Compiere
Replaces: NetSuite , Microsoft Dynamics
Now owned by the Consana corporation, Compiere claims to save users up to 80 percent versus other ERP solutions. In addition to the free version, it's available in standard, professional or enterprise editions or in a cloud version. Operating System: OS Independent.
40. Adempiere
Replaces: NetSuite , Microsoft Dynamics
Because it's developed by a community instead of a company, the Adempiere site has a little bit less of a commercial feel than most of the other open source ERP solutions. The wiki offers lots of documentation and help, but the project doesn't offer paid support. Operating System: Windows, Linux, OS X.
Replaces: Check Point Security Gateways, SonicWall Network Security Appliances, Cyberoam Security Appliances
Instead of purchasing an expensive security appliance, you can build your own with the community version of Endian's software and an old PC. It includes a firewall, application-level proxies, anti-virus, anti-spam, content filtering and a VPN. Operating System: Linux.
42. Untangle Lite
Replaces: Check Point Security Gateways, SonicWall Network Security Appliances, Cyberoam Security Appliances
Untangle protects 1.7 million people in more than 30,000 organizations with its unified threat management appliances. The Lite version is free or you can upgrade to the standard or premium versions for more features and paid support. Operating System: Windows, Linux.
Replaces: Visio
Perfect for creating org charts, network diagrams, flowcharts and other diagrams, Dia is similar to Microsoft's Visio. While it's not quite as full-featured as its commercial counterpart, it should meet the needs of most small businesses. Operating System: Windows, Linux, OS X.
44. Gimp
Replaces: Photoshop
If you need to add images to your business documents on occasion but don't want to shell out hundreds of dollars for Photoshop, Gimp offers professional-quality photo tools for free. Use it for photo retouching, image enhancement, special effects, filters and more. Note that for Windows, you'll need Gimp-win. Operating System: Windows, Linux.
45. Inkscape
Replaces: Illustrator, CorelDraw
Very similar Illustrator or CorelDraw, Inkscape is a vector-graphics drawing program that's suitable for professional graphic designers, but user-friendly enough for amateurs to use as well. The site includes links to plenty of documentation and tutorials, as well as samples of artwork created with Inkscape. Operating System: Windows, Linux, OS X.
Replaces: Halogen software, iCIMS, Ascentis
With more than 1 million users, Orange claims to be "the worlds most popular Open Source Human Resource Management Software." Paid support, services and a hosted SaaS version are also available. Operating System: Windows, Linux, Unix, OS X.
Replaces: FreshBooks, Bill.com
This Web-based invoicing system sends bills as PDF files and creates a wide variety of reports so that you can track your sales and payments. You can host it yourself or use one of the third-party hosting providers listed on the site. Operating System: OS Independent.
48. Argentum
Replaces: FreshBooks, Bill.com
Argentum offers Web-based client management, invoicing and time tracking. If you don't have your own Web server, you can purchase the software on a hosted basis for $10 per month for unlimited users. (Note that this project is not related to the online game with the same name). Operating System: OS Independent.
49. Siwapp
Replaces: FreshBooks, Bill.com
Designed to be simple and straightforward, Siwapp offers a user-friendly interface and professional-looking PDF invoices. The site includes an online demo so that you can try it for yourself. Operating System: OS Independent.
Replaces: Microsoft Office
While it's still available for download, Oracle has recently announced that it will no longer be sponsoring commercial development of the project; ongoing development has largely shifted to the LibreOffice fork (see below). Operating System: Windows, Linux, OS X.
51. LibreOffice
Replaces: Microsoft Office
This OpenOffice.org fork offers the same applications with a few new features. It's a more community-oriented project owned by a not-for-profit called The Document Foundation. Operating System: Windows, Linux, OS X.
52. AbiWord Replaces: Microsoft Word
This full-featured word processor offers nearly all of the same features as Microsoft Word, and it even reads and saves in Word-compatible formats. The newer versions of the software also offer free online collaboration for groups working on the same document through AbiCollab.net. Operating System: Windows, Linux, OS X.
53. FreeMind
Replaces: MindJet MindManager
This mind mapping software is great for brainstorming sessions, collecting research, project management, creating diagrams and more because it lets you show the relationships between words and ideas visually. And the project's owners claim its one-click "fold / unfold" and "follow link" operations are faster than its commercial competitors. Operating System: OS Independent.
54. Gnumeric
Replaces: Microsoft Excel
Gnumeric offers all of the features found in Microsoft Excel, plus 154 functions Excel doesn't have. It can also import and export files from Excel and other popular spreadsheet programs. Operating System: Windows, Linux.