There are many browser extensions for Safari/Chrome/Firefox that enable video downloading from various websites. I also was used to think OS X is a safe heaven, with almost no virus/malware. The problem is many of them does contain malwares, even on OS X, and yesterday I have had the proof. Installed Safari extension into my MPB with Mountain Lion and the HDD started to work a lot and almost block the laptop. Uninstalled immediately and all returned normal. So there are safe video downloader out here? Where can I find one?