Absolutely! You can open any Word, Powerpoint or Excel document in OpenOffice.org. Start OpenOffice.org, choose File > Open, and click the arrow by the Files of Type dropdown list. You'll see all the file formats that OpenOffice.org can open. You'll see far more than just the ability to open Microsoft Office and OpenOffice.org files.
You can also create Microsoft Office files. You can choose File > Save As in OpenOffice.org and choose to save as Word, PowerPoint, or Excel. You can also set up OpenOffice.org to always save in Microsoft Office format, by choosing Tools > Options > Load/Save > General.
This was first published in May 2006