I remember a while ago I got a virus on my computer. It was a fake anti-virus called "AntiVir" and it kept spamming me telling me I have a virus. Literally every 30 seconds or so, no exaggeration. It basically shut down every program I opened, including Chrome, so I couldn't do anything about it.
Not only that, but it kept opening IE to researcho.com and viagra.com
After about an hour I had a friend help me with it. I went to a neighbors house, downloaded "HijackThis" onto a pen-drive, and (somehow) ran it on my computer.
Cured :)