Sleep is a very technical thing, it's a 'Brain maintenance time'. It's not about saving energy or anything that could/should be bypassed (otherwise we'd be tired awake at night, useful for defending against predators in the wilderness -- nature accepts a great cost for this shutdown). I find my memory improved significantly once I started being more careful with my sleep, for instance. I wish I had come into contact with this instead of the bragging 'I barely need any sleep!' culture.
Full disclosure: I am definitely not famous, but might be considered a programmer.
I found that when hacking for a several months on a solo prototype project, my hours drifted later and later so that I ended up going to bed around 4 a.m., and rising at 11. It's really hard to correct! In terms of productivity, though, the wee small hours are hard to beat.
I'm also certainly not famous -- but I've found the same for myself. I'm far more productive between midnight and 4 or so than any other time of the day. Very hard to make those hours work with a family though.
> I often worked nights and slept during the day, but I almost always got 8 hours of sleep. There are still 112 hours left in the week!
https://twitter.com/ID_AA_Carmack/status/932718658366857216