I was standing in line at the grocery store behind a woman with a very sensible selection of products arrayed on the conveyor belt. She was watching the cashier scan each item. Then I saw her turn to her right, grab a plastic box of mints from one of those in-your-face candy displays and add it to her collection. Now, I'm not as green as I look, and I'll bet she didn't plan on buying those mints. I'll bet she didn't even give it a second thought. And that is impulse buying at its best. The store made another sale.

We've all done it. I even wound up with a really cool-looking pen I just couldn't resist when I saw it poking out of a box at the checkout of an office supply store. Naturally I didn't go in the store for that pen, and I have to admit I can't even recall exactly how it got into my bag. Understanding and tapping into this propensity for impulse buying is one of the strengths of the bricks and mortar business world. But can it become a common feature on the Internet?

Like lots of things we just sort of intuitively understand, a straightforward definition of impulse buying is difficult to come by. But you can get the gist through the words most folks use to describe it: rash, instinctive, not necessary, uncontrolled, not always smart (with the buyer characterized as an "unwilling victim"), regrettable, fun, adventurous, irrational, and oh yeah, impulsive.

In the Ivory Tower, lots of academic types have tried to get a handle on exactly what impulse buying is and why people engage in the behavior. That turns out to be a very un-simple task. There are impulsive purchasing patterns and cognitive purchasing patterns; there is “reminder impulse buying” and there is “pure impulse buying.”1 I won't even go into how impulse buying can be a variety of compulsive buying. Whew! It can all get very confusing.

I can tell you that humans are prone to purchase certain classes of products on impulse. In general, folks get impulsive about commodities (for example, food, clothing, shampoo) and make these impulsive purchases when their normal internal control monitors are compromised. People also get impulsive about stuff on sale. Ever notice sometimes price completely overrides need? I mean, only in other people, of course. And pure impulse buying is unplanned. It just happens. At least, it does out there in the bricks and mortar world.

So what about on the Internet? There's a fellow, Paul Romanchuk, who has this scheme to make online shopping a more 3-D experience in order to stimulate browsing and impulse buying.

Visitors [to a website] are made to feel as if they are walking down aisles perusing the goods. Marketers can also set up certain "trip wires" that send out appropriate messages - and these can go beyond what would normally occur in a regular mall. For example, if the user is browsing a certain section of the … store … a book on the shelf may open and close to attract the attention of the browser. Or, if you're in a music store … and you walk by a particular section, you can hear a voiceover promoting the latest release, says Romanchuk.2