if you have a patched syatem you shouldn't worry, the fix for this vulnerability was released by MS in October last year, If anyone is stupid enough not to install security updates and patches frankly it servers them right if they get infected.
There are also some tools available from Symantec - don't know if you need to be running one of their products already, though..
Search is your friend “I was having a mildly paranoid day, mostly due to the fact that the mad priest lady from over the river had taken to nailing weasels to my front door again.”
And Trend Micro has their free Housecall service - http://housecall.trendmicro.com - I usually recommend it as a first run anytime someone tells me "my computer is acting funny"...
I'm sure there are as many services as there are people on this forum, and we've all got our pet favorites.
As a side note, you can run Microsoft's Malicious Software Removal Tool's full scan from the command line. Just make sure you have the most current one. You'll see the date in the title bar. Its all in Episode 180 of Security Now. [podcast] [text] I highly recommend listening to Security Now on a regular basis.