This is what you think it is, but it might not be where you thought it might be. It is the International Airport of Vienna, the Flughafen Wien-Schwechat. When I saw it, I laughed out loud. I was the only person in the men’s restroom at the time.
Since you are seeing this as a photograph, not in person, as I saw it, I should tell you that this is not a spider. It is a decal representing a spider. The decal does everything you want it to do. It affects people who know they are being affected by it and people who don’t know. And everyone it affects is affected in the same way. Their marksmanship improves whether they are attending to it or not.
There are lots of reasons why the people who run a public facility where there are wall-mounted urinals in the men’s rooms would want pee-ers to be careful  and there are lots of ways of approaching that goal. I have seen cutesy little signs like” “We aim to please. You aim too, please.”
With appeals to “courtesy” multiplying as they are, I expect any day to see a sign that says “Please direct the flow of your urine as a courtesy to the patron using the next urinal.”
That’s really the whole event as a memory of that time. But it turns out that I have been thinking about it off and on for all the years since and I think those thoughts are part of what makes the memory so cherished.
Why not a target?
I have thought in the years since that maybe a target would be a good device. People like to aim at targets. But targets have two disadvantages that spiders do not have. First, you know they were put there in an attempt to manipulate you. Not everyone likes that. Second, if there is a place you are supposed to hit, there is the chance that you could miss it. You could, in other words, fail. Not everyone likes that either. And besides, what good does it do anyone for you to hit a target.
I won’t try to persuade you that I thought about all these things while I was standing there in Vienna and snickering in appreciation at what they had done. Some of these effects have just now occurred to me and some I thought of on the flight home. Still, there is an abiding sense that there should not be spiders in the urinals; therefore, there is an extra do-gooder credit that accrues to anyone who even tries to remove it.
Furthermore, because this is a good thing you are doing, you don’t have to succeed at it to reap the reward. And you don’t have the sense—not immediately, at least—that this was put there by someone so that you will act in a certain way. You have more clearly the sense that this is something you have decided to do yourself.
Peeing on a spider (decal) is something you wanted to do yourself. Indeed, it is something that is hard not to want to do. Peeing at—notice the different conjunction—a target is something someone else wanted you to do. Whoever put the target there.
And since a target represents an assessment—that is why some of the circles are small and central and others large and peripheral—it is something you need to do well in order to feel good about having tried. Aiming at a target and missing is really not a good thing. Aiming at a spider is a good thing (a good deed) whether you hit it or not.
So the whole thing has a feel-good aura about it. And maybe that’s why I have felt so good about it ever since.
 And if there is a journal assessing the quality of different devices for improving the marksmanship of men, I am sure it is a pee-er reviewed journal.