There was a report recently that over 70% of Thai websites carry viruses.
I got one when I visited the Jaymart mobile phone retailers website recently.
I had an antivirus running but it stealthed onto my laptop and started infecting loads of files and accessing the internet to download more. It also automatically opened windows in Firefox and IE leading to sites that sell antivirus products. It placed icons in the toolbar as well which kept issuing warnings. It was getting worse and worse!
Nothing could remove them, I tried AGV, Kaspersky, Avira and a couple of others but the viruses shut down many of the antivirus programs and stopped spyware scanners - Adaware, Malaware etc from functioning correctly.
As a last ditch attempt before reformatting my HDD I downloaded Super Anti-Spyware free version and it found and deleted most of them, allowing me to use the laptop again without irritating pop-ups or system reboots. After a couple of updates and scans it found them all.
I think it was 'Vundo.variant' that was the main culprit, but there were loads on there after it connected to the internet after the initial attack!
SUPERAntiSpyware.com - AntiAdware, AntiSpyware, AntiMalware!