Seconded. I used to use Avast, when I set up my new PC I asked a friend which antivirus to use, and he suggested MSE. I thought he was kidding.
But it turns out Microsoft actually have a pretty excellent antivirus solution here. It is totally nonintrusive - I'm less aware of it than any of the other ones I have used (Avast, AVG, Norton) and it just quietly does its thing. Recommended.
I have often benefited from recommendations for Things I Didn't Know I Wanted.
Given that Less Wrong is a community of unusually intelligent, critical, and self-improvement-focused people, I suspect we can generate a pretty helpful thread of product recommendations — perhaps even a monthly thread of product recommendations.
Rules: