Craig Denison was a Proctor and Houseparent at the American Boychoir for several years before also becoming an excellent associate musical director. He came up with most of these games, though our headmaster Thomas Thompson came up with others. Actually, looking over this list, Jihad is the only one that Mr. Denison made. He did make a lot of others, though, really!:

Jailbreak

Split everyone up into two groups: a few 'jailors' and a lot of 'prisoners'. Each jailor gets a pair of balls. Kooshes would actually be ideal for this, but soft balls that still have low enough air resistance to be aimable are good (and are what we used). If a ball touches a prisoner, the prisoner is captured and must go to jail with his hands over his head. If a free prisoner steps in jail, he shouts "Jailbreak!" and all prisoners are freed. Free prisoners may not put their hands on their head to deceive the jailors. If all prisoners are ever captured, the game ends and you should pick less dangerous jailors. Alternately, the jailors win when too much time has elapsed since a jailbreak.
There are no other victory conditions - for prisoners, try to stay alive, but also try to break your comrades out of jail. Not only will they take the heat off you, but hiding out in the bushes is no fun at all.

Jihad

Like Capture the Flag, the object is to get something, the 'holy object' from the other team's hidden temple and bring it to your hidden temple. Unlike Capture the Flag, though, there are no territory boundaries.
Each fanatic (i.e. participant) wears a life (a strip of duct tape) somewhere acessible on eir body. If a fanatic's life is removed, the fanatic is dead. Dead fanatics can be ressurrected at sanctuary, the location of which is known to all and guarded by guardian angels (game supervisors). The guardian angels may drive fanatics away from sanctuary so as to give the newly ressurrected a few seconds to clear out and not be repeatedly massacred.
Aside from the fanatics and guardian angels, there is DEATH. Death should wear all black and be extremely fast. Anyone that Death touches must give up his life and go to sanctuary. On the other hand, each team starts with one Holy Book (prealgebra textbooks work well, as does Warriner's English Grammar). Anyone holding the Holy Book may tell Death to go away, and he must. The Holy books can be stolen, and will work no matter who is holding them.
Optional rules:
Death must alternate between sides when taking lives.
When you take someone's duct tape, put it on your arm to indicate number of kills. If you are killed, you keep those strips duct tape, and they do not count as life.
You may lie about which side you are on.
Have two more Death like players - Pestilence and Famine. You should not have more than one death-type person for every thirty fanatics.

Top Gun

Play this on a soccer field, with lots of balls (soft balls that one can peg people with. In this case, kooshes are no good, because of radar deflection - see below). The Goal Zone on each side is the Aircraft Carrier of that side. Players on their aircraft carrier are invulnerable. Along the back line of each side are several 'targets' (flags). Players split up into two groups - Fighters and Rescue Helicopters (game supervisors, or you can have players swap in and out of this role in between games). Fighters can pick up and carry 'missiles' (balls) and 'fire' (throw) them, and can pick up targets. If a fighter is hit by a missile, he goes down, dropping any missiles and targets he was carrying. A rescue helicopter then comes along and runs him back to his aircraft carrier (or puts a hand on his shoulder and counts to 30), at which point he is good to go again. A fighter doesn't go down if he catches incoming missiles, or deflects them with missiles he is carrying. This is rationalized by 'radar deflection'.
If either side ever gets all five of the other side's flags, that side wins.

Bombardment

Essentially dodgeball with a net a little higher than the players in between the sides, but players can go right up to the net. This makes the play markedly different.
If you don't have a net, you can require that everything be thrown moving up and hit while moving down.

This is not a field game, and it doesn't usually have more than eight people going at it at once, but we played it.

Annihilation

Single or Multiplayer Sumo Wrestling with movable mats. Follow the usual wrestling rules. If any of your body parts ever touches the floor (as opposed to the wrestling mat), you have been Annihilated and stop wrestling. Pinning doesn't win you the match, only annihilating all opponents.
Though we sometimes played it with a few mats velcroed together, it was best when we started off across the room from each other and skoonched the mats towards each other, then leapt across and boarded the other mat and knocked the others off. Of course, if you jumped too early or didn't leave enough people behind to hold your mat down, it would slip and you'd fall on your face on the floor and be annihilated. Fun all around.

Terminator

This nighttime game follows Top Gun as being named after a movie; this game's premise is that the machines (terminators) are trying to capture the human resistance. The teams are split up into terminators and humans. The terminators have a base they want to keep the humans out of, and they also want to capture as many humans as possible; the humans start out dispersed and want to get into the base (where they have won and are no longer valid targets), but they also want to stay alive. A terminator can 'kill' a human by shining a flashlight on the victim long enough that the victim can be identified. If the first guess is incorrect, the terminator can't guess again unless the victim is still in the spotlight (if the victim was only briefly in the spotlight, the Terminator can make the first guess after the victim is unlit). The 'kill count' aspect tends to make the Terminators go ranging out, and also it helps if the base is extensive enough that the Terminators can't camp it.