It is not important at all. Really no need to worry about them. There will be a
post all over the net if a virus threat for linux is out there. They are so rare
that I been running linux for 5 years and yet to see one. See my post on avscan.

Let's consider a windows system first. An attachment could contain a
virus which we all know. However, a virus can also be contained in an
html email but not a plain text email. In the last 2/3 years it seems
that providers do scan on the server. I've tested the ones i use with a
test-virus [netscape, inbox.com, Gmail] and found that to be the case.
It would seem that the days of a virus being sent around via addresses
in one's addressbook are over.

As for Linux - fewer people use it so less likely to have a virus that
can do damage... but i'd install an antivirus package like Avast for
Linux or Clamwin. The virus's mostly are designed for windoze apps... so
instead of Word you're likely to have OpenOffice - so less likely to do
damage.

I'm no great authority but i haven't had a virus for 5 years. Perhaps
someone else more knowledgeable would like to comment.

I asked myself the same question not long ago and this is what I have learned:

1) If you use Linux and only Linux, an anti-virus package is not
important. It is generally considered a waste of resources and
bandwidth to scan Linux email and documents for virusses - it just
does not happen in practice.

2) But, if you receive email from Windows users and forward the same
message to other Windoze users, you might not realize that there is an
unwelcome payload attached to that message. Even though I am 100%
Linux, there is still an element of humiliation when a Windows user
tells me that the email I forwarded to them contained a rootkit in the
attachment. Subsequent to this experience I now also use a Linux
Anti-Virus package (AVG Free).

3) Also, if you should run a mail server on a linux box where Windows
users connect to, it is advisable to run a server-level Virus
protection for the benefit of the Windows users as well as to try and
reduce your mail traffic in not sending on virusses into the world in
the first place.

4) On Linux I also occasionally use QEMU as well as Wine in which I
occasionally run Windows programs. Both environments, but especially
WIndows XP within QEMU is not immune to virus infections. In theory
at least, since have not actually had problems. In these instances a
Linux anti-virus package might not help in any case.

I have no idea to what extent Wine or programs running under Wine can
get clobbered by Windows Virii, but maybe someone on this list would
know.

Well the program called Wine is a good lier. Why you ask? Well Wine tells a
lie MS program to run in Linux or Unix environment. When a exe file and that how
a virus or Worm will start. Tells Wine to look for the window kernel. Well,
since wine is a liar and since it is caught on lie. Wine basically go opps and
shuts down.
Wine sets up a C directory since C: is the basic directory for windows. Wine
starts to lie to the MS program. So it sets up a directory in Linux/Unix for the
program to set up shop. Some times the magic does not work and you need to tell
Wine how to lie. Thus takes some mojo to tell Wine to lie.
Lets take World of WarCraft. Or known as WOW. Leave it up to gammers to tell
Wine to run the program under Linux/Unix. Cripes! I do not even play the game,
but there is lots of people who do.
If some day and that is a BIG if. If person with too much time on their hands
will spread a virus for Linux that will take out the whole kernel. Wine may be
the way to go to send the linux or unix world come crashing down. However, since
Linux is a hall way full of doors. Like if you ever seen the Matrix. When Neo
went into the hall way full of doors. That is the same way Linux is built. With
many doors to build the construct. Linux has Gnome, KDE, XFCE or know as
xwindows. It has GNU built with in the Linux kernel.
It is going to take lots of work to take down a linux system. This is why lots
of companies are switching to Linux for their severs O/S of choice.

I think you make an important point Casper. While Linux users might feel
a bit complacent perhaps, that they are not vulnerable to virus and
other attacks we can receive and and forward mail to Widows users and
pass on infections that way. It does mean that if we want to be though
of as responsible user we should have a virus application to at least
scan our mail.

Unlike James, I do not place a lot of faith in ISPs and online services
carrying out virus protection for me, at best they filter spam with some
degree of success but cannot hope to catch much else.

While we may be safe comparatively immune from virus builders attentions
we are just as vulnerable to Phishing and Trojan infiltration as any web
user.

Couldn't a virus still exploit a browser or e-mail client for personal
info on a Linux Box? Third party browsers and e-mail clients are
different animals than the OS it's self.

A virus cannot, a hacker can. Two different things there. Can a hacker get
into your linux box? A very good one can, especially when the hacker uses
Linux/Unix to hack into any O/S there is. A virus what can turn a window box
into a zombie. A zombie is a system that has been turn over to spread spam, to
host a porn site, and what ever the author wants it to make your system do in
windows world. Yet, in linux and Unix world. A Zombie is a process that has died
but has not yet relinquished its process.
In the Linux world it is a very hard process to make your Linux/Unix box a
slave. I only seen a security post once for ubuntu and for all linux systems.
It was a hole in the firewall that allows a hacker to peep at your system. That
hole was closed so fast that a security up date was done at once. A new firewall
was in place and linux world resume. Try to get that from MS.
Most hackers in the linux/unix world do not care for a small user. Their main
goal is to poke holes into windows security.

Are you related to George Freer in Mojave?

I wouldn't worry about it...
Most viruses in windows I believe can attack due to the createobject in
javascript, where if a dll is registered you can access it with late binding
using the createobject in javascript or other language.
The registry cannot be altered by executables which download themselves into
c:\windows\system folder which is where much adware finds itself.

Since there's no such access to dll's in unix, there's no such exposure to
javascript attacks or activex objects which run in a windows environment.

Of course I would also refrain then from using
wine iexplore.exe
as well.