Have people ever thought about the afterlife?

It was comment from my mother in law that made me thinking about it. She's not a very religious person, I actually don't know what her beliefs are, she doesn't pray for people or thank god except in the way the phrase is used in Germany all the time: thoughtless, without really meaning it.*
So, what was it she said? Talking about my grandma who's in hospital and who seemed like giving up, she said "maybe she wants to be with her husband again".
My grandpa died last December.
So, if she really thought they would meet again, or if any believer believes in any kind of afterlife, how do they think it to be?
Would they still have their old, weak bodies? Or would there be a new one, perfectly healthy, perfectly able to do anything, unbreakable?
And most of all, what would they do for all eternity? Their lives were shaped by the struggles and the hard work they did. By WWII, emigration, hardship and also accomplishment.
So, what would that afterlife like, for all eternity, once you've gotten over the 10 minutes of joy to be with each other again?

* If you're talking to a German person and they're using a lot of religious language, don't assume that they are religious anymore than you'd assume them to have read Hamlet for saying "to be or not to be". We'll happily invoke god, Jesus, a soul and the appocalypse as idioms and metaphors.