I have this tendency (whether brilliant or irritating depends on my current obligations) to be very strongly influenced by works that I have recently been immersed in.
For instance, recently, I've been plowing through Princess Tutu, an anime about a duck who is changed into a girl who is changed into a princess to bring a prince's heart back to him and defeat an evil raven. (And despite the ridiculously fluffy title and the potentially-saccharine theme of the power of ballet dancing, I highly recommend it. Get through the first few episodes and it takes a swift turn for the dark and emotionally wrenching.)
Now, I'd already been sort of wanting to try my hand at some meta-fiction, but this show really brought it home for me. I want nothing more than to write a tragic old-school fairy tale wherein the characters might just actually know that they are characters and are trying to rebel against their fates. I mean, I really, really want to write something like that. I already did, then this show went and exacerbated the want.
Thing is, NaNo is in two days (cue the hyperventilation) and I've already got an idea for it. I want to write that idea. I don't think I want to change novel plans just forty-eight hours before NaNo starts.
This always seems to happen. I have an idea that I'm excited about, then I watch a movie or read a book and fall in love with the theme or setting and want to emulate it and can't at first because the original idea isn't compatible with the influential theme or setting. It's frustrating.