Open or create a document in OpenOffice. Select the text block to which you want to add the strike out effect. Right-click the selected text and select "Style" from the drop-down menu.

OpenOffice by Apache is an open-source alternative to the Microsoft Office software suite. The suite includes components for text documents, spreadsheets, images and databases.

In this article, I recreate the core of the invoice, the two tables and show how to use spreadsheet-like functions to automate the calculations. This article is based on OpenOffice.org version 1.1.