Today's night idea comes to you courtesy of a little girl who wouldn't go to bed, and a mosquito that then entered the room and wouldn't be killed or caught. At 1am we had to decamp to a different part of the caravan, and I got something like five hours broken sleep on a couch. Which lead to...
Awake (3rd Level Spell) - range of 30 feet - duration caster level+d4 days
Sleep is a natural state - it helps a body heal and a mind recover. Making someone sleep through the use of magic is straight-forward, a Sleep spell provides a gravity that a person falls into. By casting Awake the magic-user is creating a powerful barrier to prevent another from sleeping at all. If the target fails a save versus magic they cannot sleep at all. They feel tired, they feel fatigued, but no matter what they do they can find no means, natural or magical, to fall asleep.
Without sleep, the victim cannot heal, and cannot memorise spells.
After two days without sleep, the target will start to take penalties of -1 on all initiative and attack rolls. This penalty increases by 1 every two days.
After four days, the target will start to feel deep aches in their joints, will move as if encumbered (if already encumbered, this increases their state of encumberance).
After five days, they will lose a point from all of their stats; this penalty increases by 2 every three days.
Every three days the victim can make a save versus magic, and make a purposeful, concentrated effort to "find sleep" through meditation - but must lie in the centre of a circle of at least four sleeping persons to have any chance of this working.
If any stats reach 0 before the spell is broken, the target dies; likewise if they are unable to break the spell within fifteen days they die. When the spell is broken, the target will collapse into sleep immediately and will sleep for half as many days as they have missed sleep. When they wake they will have recovered any stat or encumberance penalties, be incredibly hungry, and will now be able to sleep to recover HP and memorise spells.
(Hope this makes sense, off to bed now)