There is no hiding from the fact that the search giant stepped well and truly over the line by taking usernames and passwords belonging to home owners. However, the Google privacy scandal highlights a much greater problem because the data stolen was taken from home networks that have no security set up. They are essentially left open so that anybody within range can access the network and potentially take this same information. As such, while Google did do wrong it will hopefully lead to more people using the very simple security features that are included in all routers and other home networking equipment.
A recent survey showed that one quarter of all home networks in the UK had absolutely no security protection whatsoever while nearly half of home networks could be hacked in under five minutes. Given the fact that this could be done from a car parked at the side of the road near your house, you need to that your network is properly secured.
Even with regards to things like online banking, the onus is moving from companies and ISPs to the individual consumer. If a bank can prove that one of their customers was a victim of fraud because of their own security carelessness then the bank is not responsible for reimbursing that person.
Every new wireless router includes security settings and there are simple steps you can take in order to protect yourself and your personal data.
Change the default password and the name of the network. The defaults are often the same for more than one person and an experienced hacker will have details of all the possibilities.
Use WPA encryption as this masks your password making it even more difficult to bypass.
You can also hide your network name and enable MAC address filtering for even greater levels of protection. At the very least, though, you need to set up security and add a difficult to guess password.