Early Funding Source: SBIR 0% Equity

Just found out about this source of funding for startups at the earliest stages. It is https://www.sbir.gov/ . Various US agencies have calls for proposals
Department of Agriculture
Department of Commerce - National Institute of Standards and Technology
Department of Commerce - National Oceanic and Atmospheric Administration
Department of Defense
Department of Education
Department of Energy
Department of Health and Human Services
Department of Homeland Security
Department of Transportation
Environmental Protection Agency
National Aeronautics and Space Administration
National Science Foundation
If your start up idea fits with one of the many calls for papers you could be offered up $150,000 to find out if you idea is just viable. The catches seem to be the majority of users must be US citizens and the company must be formed before application process is started. There also is some reporting to be done on where the money goes. However it take zero equity from your company.

If you have gone through this process I would love to hear your experiences.