A family member called with some version of a Vundo trojan last night. I remembered a recent conversation with John Auty where he was talking about how excellent Avast was at handling that type of malware, especially with it's pre-boot checking. (It reminds me of Dr. Solomon from the old days, and the Magic Bullet!). I thumbed back through his blog posts and found where John wrote about Avast (Part 1 and Part 2).
Avast installed with no trouble (the malware was preventing AVG from installing) and, on reboot, it fixed the problem!
I've been using AVG for a while but I may have to give Avast a spin the next time I re-install or install Windows.
The home version is free. Recommended!