Avira is again giving away its 6 month free license of Avira Premium Security Suite in collaboration with PC Advisor . Yes Avira is one of the leading anti-virus available for free with excellent detection rates and overall good performance. See more details here
Avira Personal - Free Antivirus is available for free while Avira Premium Security Suite comes with additional host of features and protections including a build-in Firewall, Game Mode, Web Gaurd, Rescue System, Anti-Bot, Parental Control and many more. You can get details here. The cost of the license is appx: 40 Euro but its available for free for 6 month from the link given above.
For the people who don't know how to get the license please see my earlier post on similar topic.