Exclusions, ignore lists, etc.

Hi all,

I had to flip a mental coin on where to put this one, since it's fairly general. But of course feel free to move it if another home for it seems more appropriate.

Most kinds of a-v and anti-spyware have some kind of list of folders and/or file types to ignore while scanning, to save time -- Ad-Aware's ignore list, for example, or avast's exclusions. With the latter, I'll typically exclude folders that are (theoretically, at least) nothing but JPG's or MID's since there might be hundreds of those files.

We all know that quite a few viruses are designed to detect specific a-v installations and disable or even delete them. Has anyone ever heard of malware which is "smart" enough to detect folders which are excluded from scans and which therefore are an inviting place to "nest"? That would seem to make for a wicked vulnerability, if there is such a thing.

Best to all,
Mike