The basis for this story first appeared on CYOC.NET. It has been seen many other places on the internet including one short branch on the "You are what you wish" story. I wanted to see a more open ended story not restricted to all of the baggage that comes with that story and this section seemed like the perfect place for it.
The little bell above the shop's main door tinkled softly as someone entered. The proprietor looked up with a bored look on his face. He wasn't surprised at all by who had entered because he had known they were coming since this morning when he was scrying in his crystal ball during breakfast. Very little surprises one who has access to visions of the future even if that vision is limited to his own shop.
The customer browsed the aisle of the shop and looked as if they were about to leave empty handed (though nobody who entered had ever left empty handed) when something seemed to catch their eye. The shopkeeper of course knew what the object that had caught their eye was and indeed had moved it that morning so that this particular customer would see it at the last possible moment before leaving.
Taking the object off of the shelf, the customer brought it to the counter and asked "How much for this flashlight?"
"That is a very special flashlight. It has magical powers you see. It can change a person's very body just by shining the light on them." The old shopkeeper said.
"Sure it does. Anyway I need a flashlight for the weekend some friends and I are going camping and I couldn't find one anywhere in town."
"You want to take it camping?" the shopkeeper asked genuine surprise in his voice (he hadn't kept watching this interaction past the point where he found out what object this customer was going to buy was.
"Yeah, so how much?" the customer asked again.
"Don't you want to know what it does?"
"If I let you tell me will you let me buy it?" A hint of annoyance had begun creeping into the customer's voice.
"Well as you can see it is a flashlight. You turn it on and light come of of the end."
"So it's a regular old flashlight after all?" the customer interrupted.
"No. Now let me finish. As you can see there are a couple of adjustments you can make to the flashlight beam. This one here," the old man said indicating the control, "will adjust the color of the light from blue to pink and back again. This one here will let you adjust the size of the beam. Any body part the you shine the light on will change depending on the color of light that you are using. Blue and the body part become more male, pink more female."
"Yeah. Sure. Whatever" the customer said, not believing a word of what the old man was saying.
"There is this one last adjustment point here." the old man continued, ignoring the interruption. "This adjusts the intensity of the color. Deep blue or bright pink to almost white. The more intense the color, the more drastic the change. Be careful with this setting though. If you shine a pure white light on somebody you could accidentally make them completely sexless and that is a terrible fate."
"That all sounds like a bunch of crap." the customer said.
"Obviously you don't believe me. Why don't you try it out?"
The customer looked at the flashlight they were holding. There was no way that this old man was telling the truth. But if it were real... think of the possibilities. Finally they made up their mind. It wouldn't hurt to give it a little test. After all, it wasn't going to really do anything. Right?
The customer adjusted the flashlight so that it was colored to change part of their body to the opposite sex, pointed it at their body, and clicked the light on.