I am prepared to pay for them as it’s not worth the risk otherwise, based on my experience with Windows.
A You’ll be pleased to hear that there’s a good reason why it’s so hard to find an anti-spyware program for Linux: the threat from spyware is far smaller when using Linux than when using Windows.
Because of the way Linux works, it’s far harder to create spyware that can get at your personal information. Also, because the number of Linux users is still relatively small, it makes more sense for spyware creators to concentrate on spyware for Windows, where they are likely to get a bigger response. The same goes for viruses on Linux – no-one has yet seen a true virus for it.
That’s not to say it can’t happen, and in future it’s perfectly possible that both viruses and spyware will start to appear. For now, however, it’s safe to go without anti-spyware protection when using Linux. Anti-virus software is available for Linux such as the free version of AVG.
There are two good reasons for installing this. The first is that you will be prepared in case someone does release a virus for Linux, and the second is that it will prevent you from inadvertently sending a virus to a friend using Windows.
One thing you shouldn’t go without is a firewall, however. Most Linux distributions will include one as standard, but make sure it is switched on and active before using the internet. This will provide an excellent line of defence against all kinds of online threats.
It is also very important to update Linux just as you would run Windows Update. Most distributions come with a way of doing this automatically.
source:http://linuxpoison.blogspot.com/2008/01/1357817580428.html