The Sheetnode module for Drupal 6 is a great way to incorporate shreadsheets as node types useful for calculators, sales tools, or a variety of other uses.  Installing the Sheetnode module is fairly straitforward according the instructions on the project page at http://drupal.org/project/sheetnode.  The only requirement is downloading the SocialCalc libarary and applying the module author's included patch.  Out of the box, spreadsheets can then be created as new nodes.  Many organizations already have complicated spreadsh

The Drupal 6 theme layer gives site builders increased control of markup to customize the look and feel of their sites. Previously in Drupal, it was difficult to override system & module markup to get a truly unique design. Thanks to an improved theming system in Drupal 6, themes can now add variables, templates, and functions to completely control markup in the theme layer. Drupal 7 looks like it will offer even more control to themers. In addition, themes get the last crack at markup through overrides to gain complete control of the design.