I just remembered another discipline technique. It's called the Ladder of Doom. Draw up a ladder on a piece of card/paper/whatever. Start your clock at the bottom rung, and work in 15 minute increments till you reach the top of the ladder. As an example, I'd start from 3.30pm when the child gets home from school, and work in 15min increments to the top of the ladder finishing at the 7.30pm bed time. Everytime the child shows disrespect, or doesn't do what they're told, their bedtime slides down 15 minutes (so they go to bed earlier). If they're really naughty, or just being stubborn about something, they may find their bedtime is like 4.30pm or something. The good thing about this system is that the child can redeem their time by doing chores when they decide to be good again. e.g. Fold the laundry, tidy their room, take out the trash, read their sibling a story, wash the dishes, sweep the patio etc. Each task gives them 15mins back on the ladder. The child psychologist who told us this idea (it was in one of his seminars) said it works like a dream. One minute you have a disobedient, willfull child, then the next minute you have a dream child desperate to make up for lost time, doing all the jobs in the house.
I haven't needed to use the technique myself yet, but I'm sure I'll need it as the kids grow and test their boundaries.