Comedian Rita Rudner did a joke that said, "My friend was in labor for 36 hours. I know, I don't even want to do something that feels good for 36 hours." Someone once described eternity in this manner: take a 10 foot diameter solid titanium ball and drop a feather on it every second until the ball is eroded away--this represents one "day" of eternity.
I was discussing religion with my 18 year old son and he said that even if he could get past the bullshit of Christianity he wouldn't *want* to exist for an infinitely long time. I had to agree with him. Even if heaven gave you an earth-like existence with beer, sex, great new books, golf, pro football, all the food you could eat, and all the knowledge you could stand, I don't think I could take it for more than say, a few tens of millions of years. Maybe a billion, tops, if the beer was really cold and the sex really hot. As to sitting around worshipping god...pfffttt, kill me, now. Some of my Christian friends argue that heaven would be just that--eternal basking in the glory of God. The thing is, the christian god is supposedly omni-present so if basking in his glory would be the epitome of great then why, if they have the choice, do all my christian friends go play golf or have sex or go to the movies rather than sit in the living room pretending they're dead, wallowing in the glory of God?
As an atheist I believe that dead is dead. I get to go back to the cosmos from which I came and get recycled as is only right and proper. But, I have to admit, that dead would be for eternity. But it would a dead without awareness so it doesn't sound so bad.
But what about you Christians, you looking forward to being fully aware for the next few trillion, trillion, trillion titanium ball degradations? What do you expect to do all that time? And remember what Rita Rudner said.