Last month I took an early Sunday morning flight from Atlanta to Orlando. I wandered into a newsstand and picked up the May 2009 issue of Popular Science, which featured a cover story about space planes that intrigued me.

The story turned out to be less interesting than the cover suggested, but I rather enjoyed another article about the discomfort of airplane seats. Overall I found the issue to be pretty good, but not good enough to carry along with me, so I left it in the seat pocket. Price paid: $4.99.

Last week I stopped on the way home at the local Krispy Kreme to pick up some doughnuts and grab a coffee. It was the first time this season that the heavy humidity characteristic of Atlanta wafted over the city, so I opted to take my joe on ice.

Once back in the car I realized that the iced coffee was sweetened -- not how I like it. I was disappointed but also thirsty. I managed to enjoy the beverage somewhat. Price paid: $1.49.

A few days ago, I released a new game on the iTunes App Store. It's a bit high concept (a port of an Atari VCS game I made), but I had worked on it carefully and knew it had been polished. I offered a good deal of context and charged the lowest price allowed by the service. Numerous trade and consumer rags picked up the story and said positive things about my effort.

Later in the day of release, I got a disgruntled email from one of my customers: "I want my 99 cents back," he wrote.

This made me start to think about small-scale digital purchases in general and the iTunes App Store in particular. When someone spends a dollar on a coffee or drops a fiver on a magazine, certain expectations are set.

Read the rest of the article over at Gamasutra.