Many people will find a new Mac under their Christmas tree this year; for some of them, it will be their first Mac. Helping a friend or family member with a new Mac can be a fun process. Not only do you get to show them all the cool features of OS X, you'll probably also help them get past some new user hurdles. This will endear you to them for life, or at least long enough to grab another handful of holiday snacks.
Screen shot courtesy of Coyote Moon, Inc.
There are many resources and tricks you can use to help new Mac users. Besides letting them know that About: Macs is a great place to find information, tips, and troubleshooting help, you can also set up their Mac to allow screen sharing with your Mac. That way, you can give them a hand from the comfort of your own home, without having to make yourself presentable for company (you might want to leave iSight turned off).
You'll find instructions for setting up screen sharing in this guide: