Hubby and I have surfed porn together. It helps that I'm bi. We've watched a couple porn movies but don't usually watch them that much since we're Busy.
Also we've fantacised about things. Not role playing exactly but talking about "What if I were to be out camping and you are hiking through those same woods. You come upon my campsite and we start talking..." You can guess the rest.
Since we swing that adds a lot of spice on it's own. Coming home to each other hasn't lost it's spark so much because it's different every time. We've also learned more about each other and what our hot spots are. We talk about sex a lot. We have fantacised about being with other girls or couples and doing things.
Also when we go out to eat or to the store even sometimes I will neglect to wear my panties. I whisper it in his ear and he gets this boyishly giddy smile. When we get home and the house is clear of kids including our daughter asleep he'll come to me and say "So what were you trying to say when you told me you forgot your panties?"
It's the little stuff. All the time. Through the day that keep each other hot. Even when he calls on his lunch break. Sometimes I'll drop just a little tidbit about how horny I am or how our daughter hasn't napped and will probably go to bed early so... Hubby gets a chuckle and once his boss even teased him asking him if he was up to something "naughty" cause he looked guilty one time. It tells hubby that I want him. He does the same for me. It takes a lot of work but once you have done a few things you start thinking of more and it becomes fun.