The Ribbon in Office 2007 has tons of functionality. You can even use it to quickly add your signature to your emails in Outlook.
Office 2007 has a new diagnostic utility to help you find problems instead of just doing the normal reinstall that we're so used to.
You can export your Access report into Excel. The integration between Office applications is really great.
Make reports easier to create with the Report Wizard in Access.
If you have to use Outlook at work, sometimes it's just easier to pull in your mail from Gmail into Outlook so everything is all in one place.
Planning a big event? Mailing labels, mail merge... it all just sounds very boring. Get through it more quickly with this guide.
I just don't understand why the default color scheme in Office 2007 is so... blah. Did you know there are sweet silver and black themes hidden away in a settings dialog?
Outlook 2003 has an easy way to clean up your inbox quickly without having to go through each email individually to decide what needs to be kept.