The backbone of both Unionist and Stored societies (for vastly different reasons), Qualia Induction is a set of technologies used to simulate an experience. It isn't a sensory override - while "pain" can be induced, and even "pain" at specific parts of the body, one cannot be forced to experience a "wound" (the induction becomes a sort of psychosomatic trauma). What it is most often used to induce is an emotion. Pleasure, happiness, joy, grief, sorrow, longing, desire, contentment, boredom, and more can all be recorded and played back for a reasonable fee.
There are many ways of inducing qualia. Even Old Earthers have their means, using BioTech and MetaTech at 3 or less to either produce a psychosomatic response or a narcotic effect (often the same thing). However, means of pharmacy before BioTech 5 often have side-effects or unwanted consequences, and MetaTech methods usually involve the subject at least being peripherally aware of the entire process before MetaTech 5 (mesmerism, powers of suggestion, guided meditation, etc.). More advanced means are available for most of the technologies. Lenses can be developed as early as CogniTech 4 that can induce qualia, while even with enough NanoTech and StringTech the subject can be made to experience certain things.
The primary form of Qualia Induction used by the Stored is a CogniTech lens mechanism that is typically installed into a virtual environment to allow that environment to produce a physiological (BioTech) or emotional (MetaTech) response. Until CogniTech 7, the experiences had to be recordings of other person's experiences - a hot dog had to be physically eaten and the experience recorded for the taste of the hot dog to be transmitted to somebody else. At CogniTech 5, existing Qualia could be edited into something more (or less) complex (such as removing the bun flavor from the hot dog, or adding mustard flavor, without producing a new experience). This technology is now used in many parts of the galaxy by many Civilizations. Pleasure lenses (that simulate dopamine rushes) are among the most addictive drugs in the galaxy, since the actual "drug" cannot be taken from the sufferer unless their dopamine glands are removed.
Qualia Induction Lenses are strictly controlled by most Civilizations. If a single memetic attack is emplaced within a lens and that lens were to become popular, it could become a super-addictive drug that slowly changes its victim every time they take it into, for instance, a pawn of another Civilization.
Tech Levels: CogniTech 4 for simple recording/playback of qualia, CogniTech 5 for simple editing of pre-recorded qualia, CogntiTech 7 for the most simple of "homespun" qualia, CogniTech 9 to produce detailed qualia from scratch. Also, BioTech 4 for gland and hormone simulation (5 for it to affect creatures whose metabolism doesn't normally function that way). MetaTech 4 for simple emotional impulases, 5 for complex and detailed emotional events (including subtle ones easily overlooked). StringTech is required to be able to wirelessly transmit this experience to another intelligence.
Cost: Depends on the complexity of the Lens and, to some extent, the Civilization itself. Cheaper for the Stored, the Union, the Taoists, and the Masquers.