It costs 1 dollar to encrypt a virus or server (for RATs etc). And it 100% FUD. There are so many FUD viruses it's amazing. And good RATs make it so you don't have admin privileges anymore so you can't end the process, and also some RAT's have word / key detecting where if you type like msconfig or Norton or so on, it automatically turns off the computer. The safest way to avoid viruses is be smart. Or when downloading a file just sandboxie it first (doesn't always work ofc but it's still nice ;P).