Laser light can be a good cat teaser ( but remember don't play for too long it might make kitty a bit anxious since they can't catch anything)
UV Black light can be a detector for urine stain or cat ringworm ( 1 out of 4 types of ringworm glow in black light. it is not a cure either. any health concern please contact your vet).
Flash light can be used for sudden power shortage. ( it is a mini torch so it is not that bright)
