usually when I come up with an idea, what grabs me about it is an element that I feel I haven't seen been done in movies before. That's what excites me and keeps me motivated to make it a real, fleshed out thing. I've made the mistake in the past of immediately checking up to make sure that the exact thing I'm trying to do hasn't already been covered. I think that is just an invitation to be discouraged and stop writing. Even though GTS started this thread about how shitty it feels when you find out that something you came up with has been made, you should finish your own work before you start worrying about what other people are doing. For all you know, you could have a much better script than the next guy's, and if not, maybe there's a germ of an idea in your writing that would never have been there if you hadn't started in the first place.