What are some lesser known tools that you love as an entrepreneur?

Hey all- everyone talks about the same tools- Notion, ChatGPT, HubSpot, etc. But I have noticed everyone has one or two favorite tools that are basically like hidden gems! For me it's always been Superhuman. As someone who spends most of the day reading emails, it helps me process my inbox faster with keyboard shortcuts specifically! So curious, what are some lesser known tools that you love as an entrepreneur? submitted