Anyone use psilocybin specifically for sleep? Experiences?

The research on this is limited but interesting. There's evidence for increased slow-wave sleep in the nights following psilocybin. The mechanism is unclear but may involve 5-HT2A receptor downregulation and changes in how the brain processes the day's experiences.

My insomnia was anxiety-driven -- the lying-awake-thinking kind. After my first session the racing thoughts that prevented sleep were significantly reduced for about three weeks. Combined with sleep hygiene work, it's been the most useful thing I've tried.

One thing worth knowing: some people report vivid dreams and disturbed sleep in the first one or two nights after a session as the experience integrates. This usually settles and then improves.