Some of you may like to try the scanning software discussed here ... http://www.theregister.co.uk/2010/02/08/se...r_shortcomings/.
As a 'second opinion' from several AV providers it does what it says on the tin. It's very light weight, cloud based and the scan is extremely quick.
Scanning is always free, and there's a 30 day free removal period, but thereafter if you at least get a positive identified you can always find something else to remove it.
The two machines I scanned came up clean so I don't think it's something that's going to throw loads of false positives at you.