The thought has occurred to me, does often, in fact. I'm "only" in my mid-twenties and am not sure I will live much longer. I have developed cancerous nodes in my throat and as far as doctors and I know, I'll be dead in a year. They grow every year, but I didn't want surgery so I'm just playing by ear. So much for a super body. From what I understand, I probably don't have time to get old and so won't plan my life around the possibility. If I make it there, cool, we'll see how things go. I'm not crossing my fingers though. (I still stopped smoking, which is proof that I'm not a total fatalist.)
Maybe if someone convinced me I had a soul, I would change the way I did things. There would be something to look forward to, in a different way, but for now I prefer to have life by the throat. That's where the bastard got me.