OrganicPop - 10:31 pm on Dec 27, 2007 (gmt 0)
Here's what Yahoo had to say:
We received your inquiry about the URL alchemy.corp.sp1.yahoo.com appearing in your web logs. That URL is associated with one of our web crawlers, which we use to determine, among other things, the relevance of an ad?s landing page. You have not incurred any click charges from this activity.