There are various specialist providers; notably, the porn industry has a huge collection of them.

Do we know the names of these payment providers? I have no doubt the porn industry must have a slew of companies supporting them.

If anyone runs a business on this list, who does your payments?

Bitcoin (through Coinbase). I produce adult games mostly as a hobby, but last year received several thousand dollars in bitcoin (not counting the price increase).

If I were serious about making money or leaving my day job I'd have to accept credit cards in some form, but for now I'm happier not having to deal with all the hooplah of setting up a merchant account etc.