DH and DS have a bit of routine at night - just a funny little thing that they say every night. DH says to DS "No crying, no play, no yelling out, just sleeping" then he repeats "No..." and DS says "crying" etc. It come about after we went through a bit of rough patch of DS not wanting to sleep without someone in his room.. It is DS's special thing that he does with his daddy and he loves it and it seems to work on him. If we have a night when he does mess around, then DH will go back in and repeat it, and then leave the room. He also has a music box that plays a light show on the ceiling and a song for 10 mins, which for us is kind of good indicator of time to go back in etc.
And although DS sleeps really well (*touch wood!!*), every Friday night DH will actually lay down on the bed with him and listen while I do the stories and then Dh will lay with him until he (yes, both DS and DH most of the time ) falls asleep. DS loves it - he is learning his days of the week so he knows Fridays are creche day and sleeping with Daddy in his room.