Well, I spend much of my time on hobbies. Instead of sitting and watching TV, I sit at the computer and score music--it's much more interesting than most television shows. The director and I will get together once a week or so to plot and scheme. We'll send email or make phone calls here and there during the week during breaks from other stuff.
I have more trouble stopping and spending time just sitting and watching a show or movie. I'll often pick up a book when attempting to do that, or I'll grab a drum to practice while I sit. It's difficult to stop doing other things and just watch a DVD or show. (Speaking of practicing, I was going to pull out a mellophone today and practice--will have to remember that in the morning!)
As I currently have no paramours--just a woman I date every once in a while and a couple of online connections, I don't have to spend much time driving elsewhere and spending face time; long email messages are all those require at this point. When I am involved in face space, then I spend less time on the hobbies and more on the relationships.
When speaking of various forms of non-monogamy...it ain't poly if you're just fucking around.
While polyamory, open relationships, and swinging are all distinctly different approaches to non-monogamy, they are not mutually exlusive. Folks can, and some do, engage in more than one of them at a time--and it's all good.