Antivirus and antispyware programs recommended for a Mac?

[green tea]

I just switched to a Mac. Can the experts tell me which firewall, antivirus, and antispyware programs are essential for Macs? Would installing any of these have a downside to my computer's performance, etc?

I want to stay as safe when using the internet as possible. Thanks

[evilfantasy]

Mac virus are not as widespread as Windows virus. But it is out there.

http://mac.majorgeeks.com/downloads29.html

I have no idea what sort of performance impact it might have.

[green tea]

Hi Evil, thanks for the link. I'll have to look more into ClamXav.