Yes, a lot of use use it.
Free anti-malware:
Dr. Web Cure-It Comodo Anti-Malware Threatfire Free Edition MalwareBytes trial A-Squared PrevX CSI Free Version Spybot S&D RunScanner Ad-Aware SuperAntiSpyware Spyware Eliminator Emco Malware Destroyer Spyware Doctor All-Seeing Eye (Monitors system - pretty annoying at first until all safe processes have been approved, but settings can be changed)
Arovax Anti-spyware Trend-Micro Rootkit Buster F-Secure Blacklight Bootzilla (Bootable anti-malware CD with many other tools.)
"Instant" Anti-virus (No installation--just download and run the scanner):
Dr. Web Cure-It McAfee Stinger Kaspersky Virus Removal Tool (This one installs but offers to uninstall after the scan. A fresh download contains the most recent virus definitions.)
PING with Clam (A bootable disk imaging CD with added anti-virus)
List of freeware security software Guide to Free Security Software (ScanComplete Site)
Virtualization Solutions (Malware attacks become impossible because either the browser or the whole operating system are isolated from the real system):
SandboxIE (Virtualizes IE, Firefox, or any other browser and works on most other programs, too)
VMWare Browser Appliance (Runs in the free
VMWare Player. The Player also will run any of 100's of preconfigured operating system and appliance images downloadable for free from VMWare, and you can even make your own VM's to run in it with the open-source
VMmanager)
Artificial Dynamics Safe Space (Similar to SandboxIE, safe browsing and protection from malware and hackers)
Fortes Grand Virtual Sandbox Microsoft Web Sandbox (Open-Source) (In development but usable)
Returnil Virtual System (The Premium version allows you to save all changes inside the virtual OS to the real system, but even the free version has a virtual drive where items can be saved outside the virtual container)
Windows Steady State (Now supports Vista, too)
Login 
General Security 
Search 
. I've never won a single software in any contest!
Facebook
Twitter
TechGuy.tv
TSG Mobile