Package tracking app
Sold 6 years later for $11,000 (and then backed out at the last second) and then shut it down.
First SaaS product. Built it while running Fugitive Toys. Was one of the first package tracking apps for the iPhone. Decided to sell it, but then at the last minute I backed out and gave the money back. I had plans of doubling down on it and then never did anything with it. In hindsight I wish I had sold it.