I have noticed a lot of people do not know that you can add Gmail to Outlook and use it as either a POP3 or IMAP (Ability to sync all your email clients). And its FREE! No other other Free email service, not Hotmail nor Yahoo, offer this awesome feature for Free. Here are very user-friendly visual tutorials straight from Google for both POP & IMAP setup :

Gmail POP Setup in Outlook : http://mail.google.com/support/bin/answer.py?answer=75291
Gmail IMAP Setup in Outlook : http://mail.google.com/support/bin/answer.py?answer=77661