CCleaner
Used to delete Avast's cookies so they couldn't spy, but of course they keep being re-applied. The information is already down wind even when deleting cookies. However even that is suspect now, because Avast's corporation bought out Piriform, the makers of CCleaner. Now I have to put up with popup advertising again, and probably now CCleaner spies on me.
Avast was supposedly good about ending that phone home feature as long as you bought the software - not sure about that, but it did end the pop up ads. I don't plan on buying CCleaner anytime soon, so you have to put up with that when using free software - I suppose it is only fair. Once Malwarebytes became an anti-virus, I had to ditch Avast - MBAM was the only AV/AM worth buying in my estimation, so now that is my only AV solution. The line between viruses and malware is so thin, it isn't worth the distinction anyway.