Have you ever had a "brilliant" startup idea that you saw realized by someone else?

It was a brilliant idea and a brilliant product. Though not my own but I did work on the idea from 2007 to 2009. This was in 2007. I had just graduated college and joined a US-based tech company called Trilogy as an entry-level Product Manager. Trilogy was a highly entrepreneurial organization. They had a BootCamp program called Trilogy University where new joinees pitched business ideas to the founder and the senior leadership. The company incubated the ones that made the most progress during the program. One such product that came out of Trilogy University was Zozoc. We used to call it Skype for SMS back then. SMS costs used to be high back then. Zozoc was a mobile application that routed your text messages through mobile internet (1G / GPRS) at a fraction of cost. (Sounds familiar) Note that these were very early days of mobile. iPhone had just launched (and without an appstore) There was no Android. Launched in China in 2006, over the years it grew to 5+ Million users across China, India, and South East Asia. However, we never found a way to monetize the users. The product was shut down in 2011 from what I recall. Whatspp was founded in 2009 and sold to Facebook for bazillion dollars in 2014.