Using Office 2003, you can integrate with the team portal in interesting ways:
Microsoft Office FrontPage 2003 - FrontPage is used primarily to customize the team portal and create analysis reports. You can also add data driven Web Parts to the portal using FrontPage 2003.
Microsoft Office Outlook 2003 - You can use Outlook 2003 to manage online calendars and contact lists.
Microsoft Office Excel 2003 and Access 2003 - Excel and Access can be used to edit lists on the Windows SharePoint site. For example, you can download the list into Excel and manipulate it in a number of ways. Using Access, you can link a list to a database table.