The story about a wireless hijacking, and this related piece about Two cautioned over wi-fi 'theft' is interesting, but sadly all too easy.

My wi-fi is protected, not only with encryption, but also by restricting by MAC address and deliberately hiding the wi-fi service. However, there are no less than five wifi services from other houses which are neither hidden, nor restrictive, and not one of them requires a password to connect or any type of encryption.