Running a business can be expensive, but your software doesn’t have to be. There are some great applications out there that are either free or open source, but are just as powerful as the expensive (read Microsoft) versions. Below is my rundown of some “must have” free business applications:

Open Office – www.openoffice.org
OpenOffice.org, or OO.org is the current king of free and open source Productivity Suites. A great replacement for Microsoft Office, OO.org consists of a Word Processor (Write), a Spreadsheet (Calc), a Database Application (Base) which is generically similar to MS Access, a Vector drawing application (Draw) and a Presentation Application (Impress). If that weren’t all, each application allows you to export PDF files, edit mathematical formulas, and create XML forms with drop down lists, checkboxes and radio buttons. OO.org allows you to open and edit MS Office files (but MS Office won’t open OO.org files). If your small business only uses one software suite, then this should be it. You can publish documents, create databases, prepare presentations, and perform complex calculations, all with this one application.

Thunderbird – www.mozilla.com/thunderbird/
Thunderbird is a powerful, extensible email client, similar to Microsoft Outlook. It is easy to create multiple identities so that you can manage your business email, personal emails, and more from a single application. One of the best features of Thunderbird is its extensibility. Add-on tools and plug-ins allow you to automate tasks, and gain more control over your inbox.

OpenProj – http://openproj.org/
This project planning tool is a direct replacement for MS Project. It even allows you to open and edit files created in MS Project. Gannt charts, reporting tools, even value analysis are all easy to create and manage. If you need to manage complex projects, then this one is for you.

TinyERP – http://tinyerp.com
TinyERP is an Open Source ERP & CRM suite. Traditionally these types of tools are too complex and expensive for small and medium sized businesses, but TinyERP was created specifically for businesses with less than 80 employees. It includes materials planning modules, accounting and finance modules and human resources modules. If you run a small shop, this tool can really help you get a handle on your business processes.

Dia – www.gnome.org/projects/dia/
I love Dia. This lightweight app is a direct replacement for MS Visio. With templates for engineering drawings, flowcharts, and more, this app really helps your documents shine. It can load and save diagrams to a custom XML format (gzipped by default, to save space), can export diagrams to a number of formats, including EPS, SVG, XFIG, WMF and PNG, and can print diagrams (including ones that span multiple pages).

These tools are all free, so download them and give them a try. You’ll find some great ways to increase your productivity, and best of all… It won’t cost a dime.