A little known Outlook print option is shown below (special thanks to LaDerick for this tip):
How do you get there? In Outlook 2010, select an email, click the File tab, and select Print. Then click the Print Options button located directly below your printer.
What does it do? When the option is selected, anytime you print an email to your default printer all the attachments will print. Sweet!
Caution: This option is a toggle that sticks. In other words, once you turn it on, every email you print will also print the attachments until you turn it off.