Biology....and metal.....mortal combat (not the game)....hatred and bitterness....growing damn near anything....pissing people off.....watching the look on a girls face when I hand her cab fair and tell her to GTFO.
Art, video games, gardening, and my most recent hobby is home brewing and learning about different kinds of alcohols. I do put them into my stories if they fit in; I don't shoehorn them in where they don't support the story though. I've got a character who is a regency-era gardener for a nobleman's estate, a character who is a mural painter, a different character who paints with oils on canvas, yet another character who paints with watercolors, a character who is a borderline-alcoholic that looks for the nearest wine bottle whenever he feels stressed, and I've got a futuristic world where people can be digitized to live inside a virtual world, then un-digitized to put them onto a new biological body.
Passions: cars, car racing, cooking, literature, my animals.
Passions incorporated into stories? I may or may not be writing under a different username