The founders of Ooomf wrote a fantastic post about how the very first version of their product was a WuFoo form and a MailChimp mailing list:
"We manually contacted the best developers/designers we knew, with the promise of delivering a stream of high quality, paid projects. If they didn’t like the work, they could unsubscribe.
We then asked our original ooomf members what development or design help they needed with their current mobile projects.
Rather than creating a fully featured marketplace with portfolios, ratings, or even accounts, we used a Wufoo form to accept projects and a Mailchimp email newsletter to send the projects out. The first week, we signed up 200 developers and designers and ran $15k worth of projects through our system. The average project budget was $2k and each one matched within 72 hours."
I love this story. In their first week, they were able to create $15,000 of transactions. How many startups take more than a year to create $15,000 of value?
From there, they iterated, step-by-step, until they had built a real product. But the key is that they always had a real business, and they were able to validate it using two free web services and a single web page.
Ooomf's first product was, to be frank, crappy. The fact that they succeeded regardless showed them that they had found a great market. A great market is one where the need is so great and the value so obvious that even a crappy product finds traction.
Before you build your insanely great product, find your great market.