I know a few people who have played the various Werewolf games out there. Last night I came across a variant called The Resistance (http://boardgamegeek.com/boardgame/41114/the-resistance). This is part of a search for mechanics I can use in the quasi-LARP setting of Grand Strategy games, without resorting to paper-scissors-rock for everything. Copying the description from Boardgamegeek:
The Empire must fall. Our mission must succeed. By destroying their key bases, we will shatter Imperial strength and liberate our people. Yet spies have infiltrated our ranks, ready for sabotage. We must unmask them. In five nights we reshape destiny or die trying. We are the Resistance!
The Resistance is a party game of social deduction. It is designed for five to ten players, lasts about 30 minutes, and has no player elimination. The Resistance is inspired by Mafia/Werewolf, yet it is unique in its core mechanics which increase the resources for informed decisions, intensify player interaction, and eliminate player elimination.
Players are either Resistance Operatives or Imperial Spies. For three to five rounds, they must depend on each other to carry out missions against the Empire. At the same time, they must try to deduce the other players’ identities and gain their trust. Each round begins with discussion. When ready, the Leader entrusts sets of Plans to a certain number of players (possibly including himself/herself). Everyone votes on whether or not to approve the assignment. Once an assignment passes, the chosen players secretly decide to Support or Sabotage the mission. Based on the results, the mission succeeds (Resistance win) or fails (Empire win). When a team wins three missions, they have won the game.
From what I have read, the plans are two cards, one is mission success, another is mission fail, although both could be mission success. So as you play through different rounds, from the iterations of success and failure, you can see patterns and hazard a guess at who the spies are.
Some potential for use as an espionage mechanic I think. Each turn the Empire can generate a few missions that need to be carried out, Agents get assigned and have a while to place their cards. At a set time, reveal cards and see if the Empire gets a bonus/penalty. After a while, someone can accuse someone else of treason for mission failures.
I am also thinking about succession mechanics for the dynasty team. While it would be nice to have a Junta style mini-game, it would just take too damn long. So thinking along Werewolf lines:
(1) All the dynasty members sit down at a table together, and close their eyes.
(2) The GM asks the dynasty players to hold both hands out in front of them. Then instructs anyone who wishes to overthrow the Emperor to slam both hands down on the table.
(3) If only one player slams their hands down, their coup fails and they are executed (lose status).
(4) If all the players slam their hands down, a full scale civil war is started, last one standing wins.
(5) If more than one, but not all players, have slammed their hands down, the GM tells the remaining uncommitted players to point towards the player they want to see as Emperor.
(6) Players open their eyes. Player with most hands pointed at them is Emperor. Emperor and supporters gain status, other miscreants lose status.
Mechanic should be resolvable in under a minute, main delay will be getting everyone to sit down and close their eyes.
Mechanics Are Easy 
What about cheating?
Princes: have a GM watching them. Cheating = loss of status.
Agents: key bit is control of the cards being handed out. Would need an NPC to track these. Less chance of cheating if the players have to choose in a minute or so.
General approach to cheating – take accusation to a senate committee and do a payer controlled trial. Guilty = loss of status.
After thinking about it, I’m not really satisfied with the Agent game as I have got it. Pulls the players to be in too many places at once, without really giving them any major role in the game.