My first experience with an ongoing game was Dungeons and Dragons in the early 1980’s. There was no ending. You just played whenever you could get the right people together. You gained in levels and collected new weapons and powers. It was an addictive game.
The next stage occurred with the introduction of a Tamgotchi pet in the late 90’s. This was a game with no ending, but with an added twist. When you went to sleep or put the toy down, the game kept playing. There was no “time-out”. Whether you liked it or not, your pet got hungry and would die. When it was dead, the game ended. Interesting statement about life and death.
After that, PC developers started making games in this genre like Sim City or Civilization. You gained in experience and powers, but the game had no set ending. Games like these usually had a time-out, where you could save your spot and continue at some future date.
Recently, on the iPad and iPhone a new series of games have been coming out. They require “babysitting” like the Tamagotchi but with a much richer set of interfaces. The UI is quite rich, like a desktop game, but the mobility of the iPad allows the developers to assume a more active and ongoing role. Games like Zombie Farms, Castle Craft and even Tap Fish all run while you are not there. Facebook even has games like Farmville that push this envelope as well.
I can imagine an implication for B2B applications. If a system had a way to credit users with learning things and giving them rankings and badges, then it could add an element of competition to learning a complicated enterprise app. There would need to be rich feedback on what the learning meant, but in theory it could work.
I don’t imagine most companies have the patience to develop such a rich world around their app, rather than just adding more features. However, I believe that if done correctly, it could add a significant differentiator from the competition and boost to usage. Not every idea will make more money, but some will. Think out of the box.