A guest account is a very easy way to access your data, so if your computer uses one, be sure to disable it. Some older versions of Windows create a guest account with access to your files automatically when you install the software. That has changed a bit now, so that the guest is disabled from the default installation. You can locate the account yourself: Find this under "administrative tools" --"computer management" or "users and groups" on most machines. You can tell it's disabled when the small user icon has a red X on it.
Step Eight: Infrared Blocking
This may seem an odd tip, but it's useful: When traveling, it's a good idea to cover or disable the infrared (IR) port on your laptop. It's handy when syncing your Palm, but it's possible to use the IR port to browse someone else's files from across a room without them knowing it. I've seen intruders access data from a laptop through the IR port at conferences, and it's totally undetectable. So disable the IR access in "computer properties" when not using it to synchronize to another device. And as long as you're blocking infrared access to your laptop, disable Bluetooth discovery mode on your Bluetooth-enabled device. Bluetooth PDAs are vulnerable to bluejacking, which exploits Bluetooth's discovery mode to drop spam -- like text, images or sounds -- unnoticed, onto the unit. It's irritating, but usually harmless. A more serious Bluetooth attack is called bluesnarfing. Bluesnarfing is like bluejacking, but instead of depositing spam on your unsuspecting Bluetooth unit, it steals your data, like contact addresses and phone numbers, and sometimes deposits viruses as well. A Bluetooth device should be configured for "nondiscovery mode." Even though it limits some of its functionality, it prevents this type of intrusion.