That's an easy one. Anything at all. Any idea--no matter how complex or how straightforward--would make a good idea for a story.

When you come up with an idea, there are only three questions you need to ask yourself. (Well that's not exactly true. You might need to ask yourself three dozen questions. What you need before you start writing are three answers.)

(1) Does this idea make a good story for these characters?

(2) Is this a story I can write? Is there something in my style, perspective, or experience that makes this a worthwhile project for me, the writer?

(3) What change will take place in which character by the end of the story?

In my own , pushy, opinionated way, I'm going to give some suggestions about these three questions. (Or, answers, if you prefer.)

(1) A story where Mulder and Scully creep through an abandoned, dusty warehouse and Mulder identifies the fugitive's whereabouts by the lingering scent of his bay rum aftershave would be tedious.

Change the story to Jim and Blair and it's a graphic demonstration of Sentinel abilities.

Change the story to Fraser and Ray and it's one more oddity on a list of ways that Benton Fraser is weirder than anyone else Ray knows.

There's room for expansion, for development of canon ideas in the second two set-ups. In the first one, unless you intend to get bogged down in an explanation of why Scully has a stuffy nose and can't smell what's obvious to her partner...well, it serves no purpose for Mulder to Smell Things.

(If you're postulating that Mulder is developing a Superior Smeller, then you have to deal with where the ability comes from, how far it extends, and what, if anything, it means to his overall quest. Not to mention whether or not to reveal it to his co-workers or boss, where, how, and if he's "trained" to use it to help him in his job, etc.)

(2) Fourteen billion people (or at least a few dozen) have written Fraser and Ray staring at each other, recognizing their mutual attraction, and tumbling into bed together. Certainly there's room for another fourteen billion (or a few dozen) more stories on the subject.

The key is that each story comes from the author's unique perspective--each author brings their own reality to writing their version of the story. Identify your perspective. What are you bringing to the table?

Are you telling the story from Dief's point-of-view because you need a non-judgmental witness who can be there at the most intimate moments? (The pro books handled Dief's POV very nicely

Do you see Fraser as longing for physical and emotional warmth and just reaching out to the person he's closest to in the world?

Is it a mutual curiosity lark/experiment that will never be repeated?

What is your story?

Look at your own life experiences, emotional perspectives, sexual attitudes. Don't, for god's sake, re-write your own first foray into sexual arena, but do search your memories for the emotions you experienced at that or another time. (This is what they mean when they say, "write what you know.")

I guess I'm saying that if you don't have something unique to bring to an idea--maybe it's still a good story idea--but just not yours to write.

(3) Tricky one. Ideally, you should be telling a story with movement--there should be a fundamental change in some character or their world and your story should describe that journey. Either in a PWP, there is a journey--usually from sexual arousal to fulfillment.

I'd say that it's key to identify the destination before you begin. We all know that where a story is intended to go and where it actually winds up aren't always the same place--but if you start with no destination in mind, you're likely to wind up no place at all.

There's a phrase for that around my house. It's call "painting the wall."

In my first Sentinel story I wanted to lay the foundation for a growing attraction between Blair and Jim, but I didn't really think much about that, assuming I'd get around to writing it into the story. Instead, I concentrated on the mere physical action of the story which centered around painting a wall in the loft.

(For those of you who haven't seen the series, in one episode a dingy white wall mysteriously showed up painted in a vibrant green. The why and how of the repainting were never addressed in canon.)

In fact, I got so involved in painting the wall, I entirely forgot to have anything happen between the guys.

The point (and I do have one) is that because I hadn't thought about the characters but only about the events--well--I wound up with a story obsessively focused on the details of how you paint while the characters sort of stood around wondering why I'd bothered to invite them.

A simple, ten-page, peripherally slashy story that's now in its fourth major re-write and still not done. Think of the work I'd have saved myself if I'd have remembered that fundamental rule--in fanfic, only the characters really matter. And no matter what the story is, the only important thing is how they react to each other as events unfold. Don't let yourself get so involved in painting the wall that you forget to tell the real story.

The really irritating thing is that I sat down tonight with a vague impulse to talk about fictional characters and mythological archetypes. Clearly I've written nothing about any of that. I guess that essay just wasn't mine to write. At least, not yet....