[ciaranm]

I use do not disturb mode between 11pm and 9am. If you're in my contacts list it'll ring (silent), otherwise you're going straight to voicemail. The concept of being woken up by phone a phone call (other than being actively on call for some reason) is crazy.

[dancryer]

Do you never worry about missing a family emergency call? Like an accident or death or similar?

I don't accept general calls overnight, but I'd hate to miss the call.

[tnorthcutt]

That's what the "do not disturb" mode is for in iOS - you can let either contacts, or favorites, through IIRC.

[ghaff]

It's absolutely essential. I travel a fair bit and I have been woken at 3 in the morning by work colleagues.