Problem
I'm a moderator on Startups Stack Exchange, and we're facing a significant gender bias in our contributors and visitors that I'd love to see evened out a bit.
Evidence
According to Quantcast, a service that monitors traffic to Stack Exchange websites, our gender divide is not particularly impressive.
Females make up around 8% of our total visitor-base. We've grown quite a bit lately, and this is in fact down from 11% a few weeks ago.
Data Scrutiny
Now, admittedly, I don't know how good that data is. They infer it based on cookies and such, as far as I understand it, so it's definitely possible that it's not that bad, or that it's worse. It's also worth noting that Quantcast looks at unique visitors to make these estimates, and not, of course, unique posters. One can infer the problem, but realistically I'm looking for more gender-balance in posters, and visitors is simply a side-effect.
I say this all not because I doubt the data, and it is in fact more than lined up with what I've experienced on the site, but I want to make it clear what my evidence is actually supporting.
Question
How can I attract more female contributors to the site?
Hindrances
As most of us know, women don't currently hold a nearly-fair (not to make this political or anything) power in most businesses, and startups are pretty similar. That said, there does seem to be a "revolution" of sorts going on, and we're seeing a lot more women in lead positions in startups.
Brainstorming
The best idea I've thought of so far is to reach out to some local predominantly female networking groups and ask them to post a link to us on their website. I can do that, but I don't know whether that will really raise the percentages or not. I'll probably do it anyway, since marketing is important to us now regardless, but I'd appreciate some way that was a bit less granular than that.