No interest in living forever but it might be nice to go on a bit longer. There would be conditions to prolonged existence..
Reasonably good health
Minimal amount of pain
Current level of mental functioning
There has to be an opt out clause. When existence becomes too uncomfortable, a quick and easy method of stopping it must be available.
I have lots of ideas to spend the extra time. Learn to play a few musical instruments, learn a few languages and expand my science knowledge. It depends if I have to earn a living during my extended existance. And do I have to keep my extended existance a secret?
I have no interest in the eternal afterlife described by various religions. The worshipping a blood thirsty monster would get pretty tedious after the first few seconds.
The Mormons have put the most thought into an afterlife. Running your own universe if you are worthy enough. Not bad but it still could get tedious. The only example we have of a being that has eternally existed is the god. Obviously, there is a big problem with eternal existance. The god is seriously mentally ill. The Chrisitian god's heaven is not the paradise we are led to believe. Look at Satan and the other fallen angels. Why did Satan decide that heaven wasn't so great?
The 72 regenerating virgins promised by Islam doesn't sound very appealing. It seems like a lot of work, having to break in a sexual partner everytime you want sex.
I have imagined that a potential heaven might be something like living in Sunnyvale Trailer Park http://www.trailerparkboys.com/
Drinking, smoking dope, commiting petty crimes and banging Lucy with no serious consequences. Except the time in a Canadian jail where you can still get drunk and smoke dope.
I never thought the believers put much thought into eternal existance. They can't imagine the downside. It is a good question to ask them, "Is there an opt out option to heaven?" I never get an answer.
I can do one thing that God can't, I can prove that I exist.