A common feature request that the Entourage team inevitably runs out of time before implementing is the ability to dial contact's phone numbers. There are several scripts/applications available that do the job that we normally point users towards.  Just released, Jon's Phone Tools (JPT), is a really slick dialer application that integrates nicely with both Entourage and Apple's Address Book. Using JPT, you can dial either through your Mac's modem or by playing dial tones into your headset using your speakers.

JPT features a cool metal interface for quickly accessing a contact's phone number and menu bar integration for a more tucked away, yet easy to access, method. Even handier, there's a notepad for quickly taking notes on phone conversations and the application is fully scriptable!  If only the notes were saved directly into Entourage and linked to their contact...