I really want to believe in karma, though I admit I don't believe in much else.
I want to think that simple laws of physics mean that if you put enough negative energy out there for other people to deal with that you will eventually get rolled up in it and choke.
Not that I'm thinking about anyone in specific right now and picturing the suffocation by karmic energy or anything, because then I would be bringing bad karma on myself, no. See, there is part of my quandry!
Seriously though, yes - I believe in negative and positive energy flows and that the more of one type you exude the more you attract to yourself. Kind of like keeping yourself in a proton/electron type balance.
If you spew all of your negative on other people then you leave a gap in your energy, so more negative has to come in to fill it. Who knows where that negative will come from when it does, or what it will bring?
Wow, that sounds really weird when I write it all down.