I like the idea that heaven and hell are simply your reaction to enlightenment. Whatever your life experience, religion, education, opportunity...a complete understanding of your role in the world could be either depending on how you reacted to your circumstances.
Take the possessive "your" out of it, and you are getting closer. It still must involve God and being judged in some way, no? How that judgement will occur, or what it will even involve is a mystery, but that is another of those things that can't be proven to exist or not exist.
BTW I would never try to take away the popular belief that you will see and be with all your loved pets and family members when you get to an afterlife, but I do find it hard to reconcile that with "state of being" rather than "place you go". But hey, that is why many very intelligent people decide to study philosophy.
Disclaimer:
Not including myself amonst the "very intelligent". More thinking of Descartes etc. I studied it, because it was great for getting chicks at parties (especially when you consider it was all I had - being a total geek and all).
:*)