OpenOffice.org for Linux
Microsoft's flagship product is feature-rich, friendly, expensive, and it doesn't run natively under Linux. Though Microsoft doesn't sell a Linux version of Office, most Linux distributions come with a variety of free office suites, and individual productivity applications including KOffice's KWrite word processor and Gnumeric spreadsheet. But nothing comes closer to matching Microsoft's suite than OpenOffice.org 2.3, which includes the Write wordprocessor, Calc spreadsheet, Impress presentation software, Base database designer, Draw vector-graphics program, and Math formula editor. All can import and export files in native Microsoft office formats, or be configured to use them by default. Windows and Mac OS X versions also available.
Note: This link takes you to the vendor's site, where you can download the correct version of the software.