ZipRecruiter advertises on a lot of podcasts. What made it different though was the CEO, who was the voice of the ad, didn't just interrupt my time, he offered me a valuable tip.
He described his own method of vetting ideas – he watches your eyebrows. When he shares an idea with someone he focuses on the reaction from their eyebrows. If they go up, he knows there might be something here. A furrowed brow and he decides to move on to search for the next brow raising idea. Easy and simple way to gauge.
The only caveat I would add is to know your audience when you administer this test. You don't want people who will support you at all costs or who just love being the negative nanny. Seek out the honest eyebrows in your life.
Being a Force for Good 