What about Sophia from Eden?

I second ES and GTO's characters.

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Hrodulf and Bjornolfr, you will not be forgotten.

And if the world were black and white,
you would be my rainbow in shades of grey.

Click 'n Play!

If I had a fantasy self, it'd be a tentacle monster.

Angel Shop, Dr. Rabbit, and Karakuri Odette have female engineers who create robots.

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Avatar by tassyn.livejournal.com

Reading: Kingdom, Sangokushi, Historie

One of the protagonists from Eternal Sabbath, Mine Kujo, is a neurologist (and has a habit of talking about odd subjects at inappropriate times.)

Sankyuu, everyone! Keep 'em coming!

In Kanon the main character is a violinist with a lot of potential.

Spiral: Suiri no Kizuna... well, it's mostly about the super smart MALE protagonist but there's like the smart girl-reporter sidekick...her name is Hiyono.
Good art too. Good manga in general.
There are other smart girls in it too.
...
Umm... if you're really willing to go out on a REALLY far limb then you can check out Black Cat.
Eve and Saya and the thief Rins are all pretty smart/cool.

Not ecchi.

I second Ray and SaiMono~

Also maybe:

Akuma to Love Song <== not quite genius, but I think she's very smart and able to keep her cool.

Kimi wa Pet <== again, not quite genius, but very smart, cool-headed and graduated from a top university.

Azumanga Daioh <== Chiyo who's in high school despite being elementary school age.

Swan Lake <== I THINK the chick from that oneshot pictured on the cover is... Can't bloody remember right now...

Akagami no Shirayukihime

Diamond Head

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How about Bamboo Blade? Tamaki is obviously a Kendo genius.

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Also forgot to add, if you consider Special A's heroine as a 'genius' (though she's also incredibly dense), you might also enjoy Kaichou wa Maid-sama!, who's heroine is smart, athletic and the top of the girls at her school.

(I know you said no ecchi, but to be honest, although I despise ecchi with a passion, I just LOVE Change 123. It has a strong main character with each of her split personalities a master of 3 very different martial arts, not to mention a pretty good storyline. Why not give it a try?~ )

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The main female in the manhwa Cinderella Boy is a genius with a very high level I.Q. The sad thing is that there's currently only 5 chapters of that manhwa out.

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Nulla in mundo pax sincera
"Always go too far, because that's where you'll find the truth." - Albert Camus

Hatsumei Princess?

Well, since you brought up the subject of Western comics, I feel obligated to make sure you're aware of Agatha of Girl Genius, and Kimiko from Dresden Codak. Also, it's probably not quite what you're looking for, but there are plenty of intelligent female stick figures in the gag webcomic xkcd.

Furthermore, I don't normally read Marvel or DC comic books, but I'm pretty sure I've come across multiple female genius characters while getting lost in Wikipedia's maze of superhero summaries, Barbara Gordon being just one such example. (It's been a while, though, so I might be misremembering just how plentiful they are.)


As for Japanese manga, I personally love Franken Fran, the title character of which is a medical genius. If you're not familiar with the series already, think Addams Family-ish black humor, but not quite so tame as that, and with a lot of "be careful what you wish for" type stories. (Yes, there's a little ecchi-ness in it, but not much. Don't let the book covers mislead you.)