Same ways builtwith.com and wappylzer

- Business people want to see what frameworks competitors are running

- Selling data analytics to business companies

- Companies who have liscened software (greensock animation, etc) and want to see if any companies are illegally using their software through CDNs.

Better free tier to make sure it goes viral. Even more important as it's appeal is limited to devs and marketing types. Charge corporate clients for volume and service. This could have been the Google of source code but you need to take the risks Google took in making their search engine free to the masses otherwise it remains a niche product.