What happens if you don't agree to TOS?
Anyway, secondly I don't understand where all the devil-with-pitchfork stuff comes from in Banks's hells. Why not just have everyone floating in blackness and experiencing the maximum possible amount of pain at all times? To prevent them from becoming catatonic you just keep resetting their brain state to the moment of their death, so they're always feeling the first shock of agony. And it scales fantastically; just copy that small simulation a billion times and run them concurrently.
Of course, there will be some philosophical problems (are two identical concurrent brain simulations really two distinct subjective consciousnesses? If so, what are the implications of error-correcting server memory that store everything twice? And does resetting someone's memory so that the same simulation plays out repeatedly actually cause the person to experience things multiple times, or is it immaterial how many times you replay it?) but that will be of no comfort to you when you wake up in the pain box hell.
I assumed that it was all cultural (note the lowercase c there) - societies would construct, using technology, the Heavens and Hells that their religions had told people already existed.
Other writers have covered the idea that higher powers might use some of their resources tormenting virtual copies of lesser beings - I'm sure this is mentioned as something that some Transcendent Powers do in A Fire Upon the Deep. Not to mention Charlie Stross's excellent A Colder War:
Not that it matters, clones don't have souls, like twins. [0]
sigh damn. Too many ideas, not enough time. Imagine if you could program in your afterlife. Imagine all the projects you could do with infinite amounts of time. Humanity's progress would get another exponential factor attached.