Backstory: One of the most influential people in my life was an older, father like mentor who helped me navigate large business deals, career switches and even person life choices. The female market always seems runner up in this department. A specific service catered to this audience would serve us well on a cultural level.
The Idea: A female only mentor network.
Deep Dive: Another two sided marketplace... you would have to get a list of mentors willing to commit first. I would target a specific geographic location. In the beginning you would have to visit local colleges to find elite mentees.
You will have to force a few of the interactions in the beginning but if you position it correctly, it should start to take off on it's own after that initial cohort.
Validation: There are already meetups, big brother, toastmasters, etc... so many different clubs and groups that bring all levels of experienced people together.
Monetization: Once you gained traction, you could sell seats to mentees. This seems a bit counter intuitive since those are the ones most likely without funds but you can pitch scholarships and pre-paid memberships to those mentors. You will keep the fee on the mentees to make it exclusive but offering scholarships ensures you'll be likely to get paid.