I stumbled upon a blog entry by mbp on The Tyranny of Skill Training, where he complains that he has to log into EVE at certain times to start the next skill training. In EVE you train skills in real time, whether you are online or not. If a skill training ends while you are offline, you are effectively losing training time until you log on and start the next; there is no queueing. Football Manager Live, the game I'm currently playing, has a similar system. But when you are not learning a skill, at least you are gathering the time as a bonus. So if you haven't learned a skill for 1 hour, and you start learning the next skill, you get 1 hour of double speed progress in the skill training. Good improvement!
Football Manager Live also has a skill planner, where you can say what final skill you want to reach, and the planner proposes the fastest way to get there, including all possible learning bonus skills and prerequisites. That *looks* like a queue, but still isn't one, you still have to learn skills manually. I guess that the reason that neither EVE nor FML have queues is that they don't want players to open an account and only log in once per month until they have a fully skilled character. That is a good idea. But the result is that you feel you need to log on at specific times, to start your next training, and sometimes that time is rather inconvenient.
So I was wondering why these games couldn't simply include a short queue, that is you are learning one skill and can already queue one next skill after that, not more. In that case you don't have to log on exactly when the first skill learning is finished. You could log on at any time afterwards, as long as the second skill is still in training, and queue up the next skill without loss of time. You still can't program skill training for long periods, but at least you don't feel as if you should log on at 3 am or lose valuable training time.