I like your multi-faceted approach and I am happy to see that according to your list I am using some pretty good security practices. And I am grateful to learn of a couple more. I did not know about Secunia PSI or OpenDNS.
I will add one more item to the list of things to keep oneself secure because I have found that it has proven invaluable: Avoid complacency and stay informed.
I say this because I notice sometimes that some people have a tendency to get comfortable and assume the steps taken to secure are adequate and they stop there. Being a busy tech fosters this complacency. However, with this ever-changing world, one day the security steps are adequate and another, they are not. For example, there are a lot of comments about using one browser over another for good security. Howerver, all browsers have had serious security vulnerabilities at any given time. In fact, I have not heard of any product (antivirus, antispyware, encryption, browsers) that has not had problems at one time or another.
I feel that staying on top of ones' game by attempting to stay informed is a good Internet security practice. I read a lot to stay abreast of emerging threats and use US CERT to try to stay informed of vulnerabilities. I know from your posts that you also stay informed.