I would absolutely love to have an open, accurate sleep tracker. I've had a total of 7 sleep studies and multiple sleep latency tests (narcolepsy, cataplexy and mild apnea solved via a tonsillectomy), and I am constantly dismayed by how poor the space for optimizing sleep is. So much so, that I may seriously consider exploring the space in a year or two to find startup opportunities. Everybody sleeps and everybody would benefit from better quality sleep.