Interesting. When I take Concerta (54mg) it makes me unable to sleep for the next 12 hours.
It doesn't make me any more awake/less tired than I normally would be, and I can lie down and kind of zone out, but I never completely drift off. Pseudo-meditation is the closest I can get to sleeping when I'm on Concerta.
I'm an extremely light sleeper and always had a very hard time falling asleep, so my guess is that concerta quiets down my brain enough that the chronic lack of sleep catches up on me.