Open Office
I’ve been using a beta of OpenOffice 2.0. (my build is version 1.9.125). I’ve used Writer (MS Word equivalent), Impress (Powerpoint) and Calc (Excel) so far, and they just work. Unlike (multiple) instances when I tried earlier versions OpenOffice I now plan to adopt it for routine work.
My IT manager cut over to using OpenOffice quite some time ago and has never looked back. He likes the fact that OpenOffice is FREE, and especially likes that it works equally well on MS Windows and Linux platforms.
Open Office file interchange compatability with MS Office is very good.