At work, I just had to reinstall all my applications (and there are lots!!) and their appropriate settings - thank God I had an external hard drive that backs up all my data) because I had a virus on my work PC.

At home, I use Norton AntiVirus 2007 which works very well. It detects and removes viruses and spyware, blocks spyware and worms automatically, prevents virus-infected emails from spreading and finds and removes hidden threats. I highly recommend