Following is list of available Free Invoicing software for SME.
- Bamboo Invoice (http://bambooinvoice.org)
- simpleInvoices ( http://www.simpleinvoices.org)
Bamboo Invoice is very simple and easy to install, Simple Invoice is having more features but few of them don’t work, for example delete functionality is still not complete. Bamboo Invoice has small set of features but works perfectly. I prefer using simple invoice, since it supports more features and more documentation is available for simple invoice.
prabhusrivastava 