Your Best Tip or Trick for Protecting Your Computer

[sherryinutah]

As long as we access the internet we're at risk of allowing something or someone to "mess with" our computers. 

My best trick is to password protect my administrator account and then use the guest account to surf and work online.  That way noone can make changes to my computer (remotely or otherwise) without logging in as the administrator.

What do you do to protect your device?