I was playing with Google's new search options  today, and I realized that search results for "related searches" was using some pretty goofy matching. Here's a normal SERP for the phrase "keyword tool" (click for full image):
So far so normal. Then we click over to search options:
Note the inclusion of a strange ad amongst a lot of ads that make sense.
Now let's drill down to "related searches" for this query:
Google appears to use a different algorithm for search network partners, is that the case here? I've also seen the new search options be a bit buggy (in IE 8) so maybe this is a part of the perpetual beta phase that's being rolled out?
I'm not sure how many people actually make use of search options (the text link seems to blend in), but it seems that this would be an instance where bidding on Google.com search results could be causing your ad to show against some suspect stuff.
Anyone seen anything like this, or have a better explanation for the behavior?