The startup which does not have to spend even a nickel on marketing is the one which will have a ball if they now only have a great gem product.
37Signals when did RoR, I believe they had nothing to spend for marketing. The RoR gave them a huge audience.
And that gave them a ball for the gem of a product called “Basecamp.com”.
SaaS wins if you have a direct audience.
Make something open source, in this case a technology and charge for the SaaS product.