I like a good conversation topic

you probably do too.

they pass time when you are in a situation without constant entertainment. I like to turn my TV off every now and then, so conversation topics are useful.

some good ones:
what is the greatest scientific invention?
- note, this one has a tendency to wander off topic into the definition of scientific invention and the necessity of one invention for another. you end up with the plow or some other simple tool that created the time/space/beginning for other inventions. barely anyone chooses nuclear reactors. we think old ideas are better than new ideas. But, importantly, if your conversation goes off the initial topic, that is OKAY! the purpose of a conversation is to talk and listen, in turn. you should be interested in the things being said to you and have something to say in response. if you don't, then you should change the topic to something that you do have responses for. If you can't think of anything that you could converse about, then you should depart. Those of us with conversing skills need skilled others to be with us. you are taking up space in our conversation circle.
Are we ready for a major disaster to strike?
- a good conversation topic will bring up other topics, like what sorts of things do I need for a disaster? What is a likely disaster for my area? what would happen if we got hit with a freak tsunami instead? Which dog would we eat first? that sort of thing.

conversation topics can involve a suspension of belief, like when you go to see a play and you have to pretend like the people in front of you are actually 1930's era New Yorkers. A good example of a conversation topic that requires some suspension of belief is
What will we do when the zombie apocalypse comes? should we run or should we hunker down to defend?
- if involved in a suspension of belief conversation it is only polite to take the topic seriously, but don't be contrary. for instance, when the question gets posed: how fast do you think zombies can run? this is important to the fight or flight discussion, try to put some thought into it. don't be a jackass and make fun of the topic by smartassing back that a zombie runs as fast as a zombie can do anything, which is not at all because they don't exist. you, my friend, are no fun and not a good conversationalist. I hope you are front and center when the zombie apocalypse starts.