If you are like most Seattlites, you have a wireless access point transmitting and receiving your data for all the world to listen to. If you are smart, you will encrypt this traffic using WPA2 using a complicated passphrase involving letters, numbers and symbols. If you are really cagey, you won’t transmit information wirelessly at all but use ethernet cables.
The reason for this paranoia is that there are entire linux distributions written for the express purpose of decrypting your passphrases and gaining access to your wireless network, where various actions of ill intent can be taken such as hijacking your internet sessions with facebook or even worse your bank, accessing your financial records and important information about you that can be used to steal your identity, etc. This can also be accomplished by those with less technical knowhow by applying elbow grease and digging through your trash.
How to prepare against this possibility? Put a passphrase on your wireless internet. Shred important documents. Practice good computer security, i.e. don’t set up data shares without passwords on your home network.
There are programs available that can let somebody crack WEP in a few seconds flat, if the password is easy. Likewise for windows user passwords. Therefore, use strong encryption like WPA2 and use complicated passwords, and especially don’t use common passwords like the word password, because people who like to compromise networks have built dictionaries (called rainbow tables) of the most common passwords and can cycle through the 5000 most common ones in ten seconds.