Leave it to Sue Citro to come up with the random link that turns up pure gold.

This Very British usability firm did a 5-day eye tracking marathon looking at some of the UK’s top e-commerce sites. its findings are easily generalizable to U.S. non-profit best practices.

Here’s one useful nugget: Eye-tracking specialists have repeatedly noted the powerful draw of a picture of someone’s face — they argue we are hard-wired to look at faces, and that that ancient programming comes very much into play online.

Here’s what the firm, etre, has to say:

Those new to eye tracking may be surprised to see that visual activity in the main area of the page revolved around the three faces. The faces of the two women and the little girl were seen by more than 35% of our users – and even distracted these users from looking at the clothes they were wearing! This behaviour is very common – in fact it’s a wired response for nearly all of us. Due to the importance of facial identity and expression in terms of social communication, humans have developed a strong compulsion to look for faces (this compulsion is so strong that we sometimes see them in places that they don’t exist, for example, in clouds or tea leaves). Thus, on a webpage, faces are typically the first thing that users head for.

Got any ideas for the call-out box on your next email appeal?