Google

The resources provided at no charge from Google are incredible.

Google Docs allows you to not only use a word processor and spreadsheet tool that is free, but it is also a collaborative platform. media type="youtube" key="eRqUE6IHTEA&rel=1" height="355" width="425"

Google SketchUp is another example http://sketchup.google.com/

Google Earth is yet another example. http://earth.google.com/

You can find additional tools at Google Labs. http://labs.google.com/