The National Security Agency (NSA) has published a document [PDF, 500kb] outlining 'Best Practices for Keeping Your Home Network Secure' - are you following the NSA's best practice advice?
The document provides a good overview of what everyone should be doing to keep their systems safe. If you're a hardcore geeks then there won't be anything here that you won't know about already (whether you follow the advice or not ... well, that's up to you), but for the average home user, there's an absolute mother lode of information in the document.
Much of the information is common sense - keep your OS and applications updated, run security software, use good passwords and use SSL encryption on the web. But some of the information is a little surprising. The recommendation to use full-disk encryption is interesting, as is the warning that cellphones equipped with cameras could be storing your location in photos. The advice to enable data protection on the iPad (which equally applies to the iPhone, but the NSA don't mention this) is also sound advice but somewhat of an interesting, and very specific, tip to choose to highlight.
Good document, a bit light on actual 'how to' details, but still a good security primer.