Crystal ball of fixation
A crystal ball of fixation is an evocable item which, when used "successfully", leaves you paralyzed and slow for 100 turns. This makes you easy prey for any wandering monsters that find you. On a failure, you suffer a Divinations miscast effect, such as losing all MP, taking intelligence damage, or being confused for 10-20 turns. This item serves no purpose except to make players cautious about testing unidentified crystal balls.
History
These were removed in 0.8. Before that, they were a source of numerous amusing deaths.