Well my top 2 would be Spybot - Search & destroy and Ad Aware nonetheless I have removed Ad Aware after 4 years of using it. The new version of Ad Aware was so bloated and fancy that it froze my computer. I'm still using Spybot - Search & Destroy. How could I forget ... I'm also using Spyware Blaster. Love Spyware Blaster.
You should visit
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Cheers,
JJ