Carmaggedon had some psychadelic colors on the screen and the camera moving everywhere when taking a drug power up.
RPG like Bladur's gate also reduce the player's field of vision by increasing the 'fog of war' when you're blinded. (the interface is not affected though...)
Anyway, how would this system work when you cast a blind spell on a computer controlled enemy for example? You would need different impairing rules for the AI.