There's some folks that farm lobste.rs -> HN. Actually just one in particular. They're now in the top10 using this strategy due to how effective it is.
I'm yet to see the first karma ATM, where they can withdraw their karma and live a life well earnt!
I confess, I'll sometimes check out lobste.rs/recent and if there's anything interesting, pop over here to submit it.
Definitely substantial overlap in terms of posts that are interesting.