Unobtrusive? Ha!

When I went to D.C. this last Christmas, and visited my dad, he had no fewer than 4 spybots on his computer, which was slow, leaking memory like Windows 3.0, and crashed more than a Ford Explorer with Firestone tires.

Pulled out all the spycrap, and he's been running fine since. (Gator, aureate, and a couple others I don't remember.) The leaks have pretty much stopped, his computer is noticeably faster, and he doesn't get the random bluescreens he used to.