Backstory: Every time we go to an event we come back with tons of business cards, some blue, red, purple... most are white. Often the cards are tossed in drawer or discarded. We lack any context to what we discussed with the person and this presents a huge waste of paper.
The Idea: Create an application where someone can enter their email or phone number and they are sent your virtual business card. You instantly form a deeper connection by exchanging personal information.
Deep Dive: The app would also allow you to create a note and attach it to the newly created contact, giving you context for the interaction. Further versions could include integrations with CRMs like salesforce and tag the user as a "lead" and any event specific information you configure.
Validation: A mentor asked me to send over my information to create a virtual introduction. I snapped by business card and sent it on. The third party responded with "Nice card, let's chat tomorrow." I think people are ready to adopt a more virtual form of business information exchange.
Monetization: Have custom branding on the initial and free versions. Allow users to pay something small, $9/mo to remove branding.