Those sissy boys in the army, they gotta have their 'bots and guns, shiny vehicles and iron suits. Me, I don't need none of that. I've got everything I need on me.
Cagle, Claremont Class Biomod Mercenary
The PCs find a strange helmet, when donned it will take control of that PC and speak and act trough him/her. It explains that it is benevolent and needs their help in a quest and that it will stop possessing the PC when the task is done. Great if a player is gone for a number of sessions.