* In the Sharing pane of System Preferences, enable Screen Sharing, File Sharing, and/or Remote Login (according to your needs). If you're a MobileMe subscriber and you'll have access to another Mac, go to the MobileMe preferences pane, click on the Back to My Mac tab, and start Back to My Mac. (Back to My Mac lets you access resources on a remote Mac without knowing its IP address or giving it a domain name. Here are some troubleshooting tips.) Otherwise, consider installing the LogMeIn utility (free; Pro2 edition, $70 per year) to give yourself remote access from any Web browser.
* If you think you might need to access your home or office computer remotely, be sure to leave it turned on when you leave. In most cases, even sleep mode prevents remote access, so disable sleep (in the Energy Saver pane of System Preferences) and turn off your Mac's display.
4. Turn on an out-of-office notification
If you'll be unable (or unwilling) to check your e-mail while you're on vacation, you may want to set up an automatic reply to let your correspondents know you're away. The best way to do this is to set up a vacation or out-of-office message on your mail server. Exchange servers, MobileMe, and Gmail are among the many mail servers that can do this. If in doubt, check without your e-mail administrator. (You can also set up an automatic reply using a rule in an e-mail client such as Apple Mail or Entourage, but these work only when your computer is turned on and awake, with your e-mail program running--which may or may not be true when you're on vacation.)
* For MobileMe, log in to your account at www.me.com, go to the e-mail page, and choose Preferences from the pop-up gear-shaped Action menu. Out-of-office messages are found on the Vacation tab of the new Mail interface.
* For Gmail, log in to your account at www.gmail.com. Click the Settings link and then click General. Select Vacation Responder On. Then fill in your message and other details and click on Save Changes.
* For Exchange accounts that you access via Microsoft Entourage, select your account and choose Tools -> Out of Office. Select Send Out of Office Messages, enter the message, adjust any other options to your liking, and click on OK.
5. Change your voicemail message
Last but not least, change your voicemail message to indicate when you'll be back and what the caller should do in case of emergency. If you don't normally retrieve your voicemail remotely, be sure you learn how.