This is mostly aimed at the common end user. That doesn't mean that "experts" or "power users" won't find useful information here. I do a lot of system cleanup in my line of work, as an IT consultant (primarily for small business networks), and while this isn't anywhere near a comprehensive list of the sort of utilities I use, it is certainly a decent list of things for the general end user to consider in protecting his or her computer from malware running rampant on the Internet.
I actually wrote up a fairly solid post on the subject elsewhere, and I decided I'd put too much into it and it was too well put together for me to just let it fade into obscurity there, so I'm making it available here as well. Here's the link: