There are a couple of open source accounting applications available:
Aria is a PHP-based application that uses MySQL as the storage mechanism. The interface is Web-based, enabling access without specialized client software. It offers a lot of the functionality a small business like yours requires, including payroll, invoices, and inventory.
A second alternative is SQL Ledger. It offers much the same functionality as Aria. It is based on Perl and PostgreSQL.
You mention other financial applications for your company. Without more detail, it's hard to provide firm guidance, but some typical areas companies might be interested in include ERP and CRM applications. There are a couple of options in those areas. For ERP, Compiere is a pretty well-known open source application. For more detail on it, please go to my answer to another ATE question. In CRM, SugarCRM is a recently released open source application that's getting a lot of attention. I expect to feature SugarCRM in an upcoming Golden's Rules column, so keep on the lookout for it.
One of the biggest advantages all these applications provide is the ability to run on Linux. Many of the financial applications for small-to-midsized businesses are pretty firmly wedded to Windows, which forces organizations to keep a mixed environment shop, which can raise operations costs. Therefore, it could be well worth your time to check into these applications.
This was first published in November 2004