Many of us are employed deep within corporate IT departments; I'm actually a Regional Chief Technology Officer. Like everyone else, we, too, have our share of the "effects" of spyware, or better yet, I like the term.... "cr*pware". For home users, it's easy to use the free-to-use products, but that's not so easy for corporate or government users. We seriously enforce software licensing; thus, without purchase, most all of the anti-spyware products cannot be used.
Purchasing itself isn't the issue, but we don't like to buy licenses one by one. I'd like to find an enterprise solution where seat licensing is more affordable. However, our experience is that no one product usually seems to be enough. It often takes a combination of two or three products to clean a system once it has fallen victim, occasionally more. Of course, if my pockets were deeper, an enterprise license for several products might be what's necessary. However, my pockets aren't deep.
What's your suggestion for the corporate world? Do we use the hosts file route which, by the way, I have used on my kids' systems, for all systems and then use software products for cleaning problem machines? What kind of performance hit does a system take with thousands of lines in a hosts file? What to do, what to do....