"Mankind has not changed at all"

That's not what Neil Armstrong said when he took a leap on moon

I think the two biggest modern day sins are following or falling into the hands of corrupt minds who are out for nothing but lies and scams and also relying on the newest technology in consumer markets to progress the future. Eventually everything will be run by machines, when that happens most people on earth will be considered useless and lots of people will die for they will become a waste of resources for the important ones. Sounds crazy but just look at phones and computers got us, you no longer need real life friends nor do you need to write letters by normal mail. Its a process of elimination, those inventing the tech know what they are doing or maybe they don't, maybe they are too blind by the dollars to see where humanity is headed.

I don't know what you mean by "modern sin", since there is nothing new under the sun. I think sins have always been either the same, or repackaged to look slightly different.

Totts : Nothing is new under the sun, as play4fun said before me. Modern sins are exactly the same as before. I'd have to say that the most dominant sins in our culture, though, are apathy, lust (and flippancy with marriage/relationships), and laziness (everyone wants someone else to take care of them- welfare, welfare, welfare).

BTW, welfare is acceptable in some situations. I'm referring to how many abuse it and use it either because they feel someone else should provide for them OR they exploit those on the system to gain power.

I'm not sure certain if modern sin is the best term?
As a christian technically once saved we are no longer sinners. We are saved by grace and are simply God's children with a sinning problem. Or something to that effect is how it has been expressed to me.
Sin has not changed in essence ever. If to have though it is to have done it then each thing we do now is as bad as it always was. There is simply no need to increase what we consider to be wrong by announcing them to be modern sins.

Am I making any sense here?

Exactly as play4fun pointed out.  Same sin, different package.  The only difference is that today we have the media and internet that floods us with information and this is available at a click of a button.  I'm specifically thinking of the abomination, pornography.  Example:  when I was much younger, around 10, I had no idea something like that existed.  Today kids are having sex at the age of 12!  It has always been around, we are just much more exposed to things like that today.  Also, the world has become desensitized to sin.  Lines are "purposely" being blurred between what is right and what is wrong.

What Play4fun said.

And no I don't want to go into any specifics thinking some other form of sin would be now more prevalent than any other. It has always been like that and it is still like so. People just think the olden days were somehow better in this sense but they were not.