If you've ever played Paranoia, you know that player characters in that game come with six clone backups, which can "respawn" the character in the event of death. This is necessary because life is incredibly cheap in Alpha Complex, the city of the dystopian near future, and PCs tend to die several times during every adventure.
In the original edition, the clones are treated as sort of "magical", in that they are held off-screen until needed (i.e. when a PC dies), and then a replacement clone will appear in a convenient location, ready to take over. The clones monitor the original PC, so they know what the original knew. The place where the clones sit and wait to be activated is inaccessible. It's essentially just a story justification for the game mechanic of letting PCs have multiple lives.
But imagine a game of Paranoia in which the PCs can somehow enter and interact with the clone backup storage facility. They can find their clone backups, talk to them, and release them. And maybe team up with them. If you're a Paranoia GM, and want something unusual for a new adventure...
Mark: But clearly I'm not needed just yet. You continue on.
R2-D2: Clone backups. That's some A-grade paranoia, right there.
Luke: I don't like this. It's creepy. Can I get rid of the clones?
R2-D2: You should fight them to the death. That'll get rid of all of you except one.
Luke: What? I don't want to do that!
Mark: Sounds good to me.
R2-D2: You get the XP from killing all the others, and it doesn't matter which one wins because you just play that one.
Luke: Oh, that actually sounds good. Let's do it!
Mark: Wait a minute...