Even though popular, free Email programs--such as Mozilla Thunderbird--may have built-in spam protection, I encourage you to consider using special programs like POPFile (http://popfile.sourceforge.net/) or K9 (http://keir.net/k9.html). Essentially, these programs are more than just spam blockers or fighters. They are an automatic Email classification tool that works with all incoming Email messages. If you can check your Email using a POP3 Email client, like those mentioned in response to question 9, then you can use them. Using Bayesian filters, they allow you much more flexibility than simply classifying Email as spam or ham, good or bad. Instead, you can use it to build a set of powerful filters that work in tandem with your Email program. With one of these two free programs in place, thousands of spam messages--with viruses--are quarantined or sent straight to the program's trashcan each day.