OPEN OFFICE

If Microsoft Office has Microsoft Office Word,
Open Office has Open Office Writer.
Open Office Writer-It has everything you would expect from a modern, fully equipped word processor or desktop publisher: powerful features like AutoCorrect, AutoComplete, AutoFormat, Styles and Formatting, Text Frames and Linking, Tables of Contents, Indexing, Bibliographical References, Illustrations, Tables, and other objects.Writer is simple enough for a quick memo, powerful and stable enough to create complete books with lots of graphics, headings etc.
If Microsoft Office has Microsoft Office PowerPoint,

Open Office has Open Office Impress
Open Office Impress- It is a truly outstanding tool for creating effective multimedia presentations. Your presentations will stand out with 2D and 3D clip art, fontworks, special effects, animation, and high-impact drawing tools. A multi-pane view puts all the tools at your fingertips, and you can 'park' your most commonly used drawing tools around your screen ready for single-click access. Share your work in many ways: not only pdf, but also html and Flash.
If Microsoft Office has Microsoft Office Excel,
Open Office has Open Office Calc
Open Office Calc- It is the spreadsheet you've always wanted. Newcomers find it intuitive and easy to learn; professional data miners and number crunchers will appreciate the comprehensive range of powerful features including Advanced DataPilot technology, Natural language formulas, an Intelligent Sum Button, a comprehensive range of advanced spreadsheet functions, Styles and Formatting, and a Scenario Manager for "what ifs".
If Microsoft Office has Paint,

Open Office has Open Office Draw
Open Office Draw- is anything from a quick sketch to a complex plan. Drawgives you the tools to communicate with graphics and diagrams. Manipulate objects, rotate in two or three dimensions; use sophisticated rendering to create photorealistic images. Smart connectors make short work of flowcharts, organisation charts, network diagrams, etc. Styles - a common OpenOffice.org feature - help you control your work easily and precisely in Draw.
A Draw image is worth a thousand words!
LASTLY:If Microsoft Office has Microsoft Office Access,

Open Office has Open Office Base
Open Office Base- it enables you to manipulate database data seamlessly within OpenOffice.org 3. Create and modify tables, forms, queries, and reports, either using your own database or Base's own built-in HSQL database engine. Base offers a choice of using Wizards, Design Views, or SQL Views for beginners, intermediate, and advanced users.