James Altucher, who's posts used to appear frequently on HN maybe 6 or so years ago and had a few good ones about how he would write down every idea (10-20 a day) and his methods for validating them. I haven't read anything of his for a while, but he still seems to write a lot about ideas.

https://jamesaltucher.com/blog/the-ultimate-guide-for-becomi...