Bitdefender, the market leader in security products offers several free utilities for your security needs that you can use absolutely free.
1. BitDefender Antivirus free edition: An on-demand virus scanner that uses its award winning malware scanning engine to ensure high detection and removal of all viruses from your PC.
2. BitDefender Anti-Phishing: It gives protection from phishing attempts. It can block malicious web pages that used to steal credit card data and other personal identification information. It supports IE and Firefox browsers.
3. BitDefender Chat encryption: Another free utility that keeps your instant messages safe from hijacking through a simple and automatic encryption process. Supports Yahoo! Messenger and Windows Live Messenger.
4. QuickScan : Another free service from BitDefender. It uses both local and cloud scanning to ensure a good detection rate. It detects running malware from a webpage very quickly than other similar tools.
5. Saf.li: This is a URL shortening service from Bitdefender that not only creates a short link, but it also scans the content of the corresponding page for malware and phishing.
6. Free Virus Removal tools: BitDefender offers several free tools for removing specific viruses from your computer.
Hope the above list may helpful to you.