Banner Ideas

part of the ArsDigita Community System by Philip Greenspun

The Big Idea

A banner idea is something that you can place randomly on pages enticing readers to click to a different, potentially unrelated page. How is that different from a banner ad? A banner idea Why use banner ideas? If you have a bunch of users working themselves into a rut in a particular corner of your site, you can use banner ideas to show them the interesting content on other parts of the site. For example, on, I use these to try to get people to go from the boring classified system

Under the Hood

As a developer, all that you have to do is call bannerideas_random and include the result in your page output.

Note that when a user clicks the "more" link from a banner idea, the click is logged in the clickthroughs column of the bannerideas table.

To save wear and tear on the database, the banner ideas are pulled from the database and cached in RAM for one hour (by default).

The Future

We keep a set of keywords associated with each banner idea. Suppose that the banner ideas are being placed below a discussion forum thread. The right thing to do would be to look at the words used in the discussion and pick a banner idea that was related to the thread.


I built the banner ideas system in order to test my theory that human beings will accept, without complaint, an unlimited amount of commercialization. That one can stuff flashing banner ads in every corner of a page and nobody will comment. The other side of my theory was that unfamiliar ideas would drive people crazy.

I tested this theory by putting crass animated banner ads at the top of some pages in the LUSENET system at I put banner ideas at the bottom of other pages and also put them into classified ads at The result? Not a single complaint about the garish commercial-ish banner ads. Huge volumes of email complaining about the ideas.

Here's one from someone who has concluded that was started to be some sort of commercial trading post:

You're site is great, I have been using it for a long time and
have bought/sold many many items. I also enjoy the equipment reviews and
travel pics.

Please take the following in a friendly manner, and as a request from
someone who obviously thinks differently than yourself.

Recently you began adding small "ads" at the bottom of other people's
ads. Some of the ads you have posted are very offensive to me and I
would greatly object to them appearing along with one of my ads. The two
I saw today include references to a God that created man-man, man-woman,
and woman-woman couples. To me it is blasphemy, and dangerous to a young
mind, like my son's who I allow to peruse your site. The other ad seemed
to promote anti-social behaviour, encouraging one to have fewer
"transactions" with others.

I love your site, but if these ads continue I will be forced to use
other avenues such as ebay to enjoy my photo buying/selling habits. 

Again, thanks for a great site, but let's keep it free from these very
personal opinions....
(this author was referring to an excerpt from Aristophanes in Travels with Samantha and a reference to my avoiding litigation article)

Here's another one from a railroad group:

However, some members of our group feel that a portion of the material 
being presented is a little too controversial to expose to people who 
are expecting to see only railroad content.  We are not out to advocate 
any positions one way or another, just talk about trains.  For example, 
someone reported a message pointing to a militia Web page.  It's fine 
with us that militia groups have Web sites, but we figure people visit 
our site to take a time out from such weighty issues.  We would prefer 
for people to locate those on their own.
This was provoked by a reference to the community chapter of Philip and Alex's Guide to Web Publishing, which uses the Michigan Milita to make the point that most organizations spend most of their time on education, even if they wouldn't be thought of as primarily educational in nature.

I think my theory holds up. A lot of folks can't stand unfamiliar ideas! What I did not expect is how much difficulty many people have in reading comprehension. The most virulent complaints were from people who had simply misunderstood the banner idea or the linked-to article. This can't be a matter simply of literacy because the same people were perfectly capable of writing a grammatical multi-paragraph complaint.