Talking about this? -> Clamwin I was using it under Spyware Terminator months ago, it was nice, but don't know about having it as standard AV. Edit:// Hmm it does not provide real-time scanner
ClamAV is a second tier AV at best, but NOT "useless". ClamAV runs on *nix only. It is widely used on *nix-powered email servers. ClamWin runs on Windows. ClamWin does not include an on-access real-time scanner. You need to manually scan a file in order to detect a virus or spyware. As gery commented, there are better free choices.
Yes, but there are also worse paid choices. The highly respected German magazine c't has recently done a test of various AV programs (in collaboration with AV-Test). It's true that ClamWin didn't belong to the top group (c't recommends Avira AntiVir Premium, GData Antivirus and Norton Antivirus). However, they said that ClamWin has improved a lot in the past years, and it's remarkable that in the test it was higher rated than CA Anti-Virus, PC Tools Threatfire Pro and Trend Micro Internet Security - all of them paid products.
MoonSecure is an AV based on ClamAV with real-time protection. Its pro are that it's free for commercial use (it's the only one, together with Comodo -and probably it's better than comodo, for now), and that it's decent; its cons are that it's much worse than many other antivirus, and that the GUI isn't very nice..
Clamwin portable is a very useful backup scanner. A) Good detection; it found Vundo on my computer. Avast!, McAfee, Ad-aware, and Spybot failed. Since Clamwin can only remove, not disinfect a file, I let Norton 360 remove Vundo.
I use it on quite a few UTM appliances.....firewalls, they do the scanning of http and mail traffic. So it's a good 2nd layer of defense..that has ZERO performance impact on the workstations.