An another alternative to Microsoft Office.

Softmaker is a german company. Its Office suite is available for Windows (XP, Vista, 7, or CE) and for Linux (easy to install on Ubuntu).
It has tabs, just like Firefox. And it is very fast and reads very well Microsoft files.
The text format, for example, is ".tmd", but you can save it under a lot of other formats, including .odt.
I use Softmaker Office for middle-sized texts (for books, I prefer OOo), and because it is always interesting to use other softs than "classics" like Microsoft's and OOo's. I find here some reminiscences of the Amiga world.