Having a personal trainer has helped me immensely with the boredom factor. I really look forward to the days I work out with my trainer because that hour flies by. I'm exhausted, I'm challenged, sometimes I'm even scared, but I'm NEVER bored. Every workout is different. I consider my personal trainer to be the single most important factor in my success.
Another thing that helps immensely in terms of boredom is intervals. On whatever cardio equipment I'm using--elliptical, stepmill, or treadmill--I do one minute at a really high intensity then one minute at a recovery pace. I do this for 10 to 20 minutes, depending on the equipment, then move on to another piece of equipment. During that one minute at a high intensity, I might feel like death is imminent but I'm sure as heck not bored. Needless to say, the 1 min recovery flies by. You'd be surprised how fast 20 minutes goes by when you pace it out this way. And it's a better workout than steady-state cardio.
Finally, another thing that helps me is taking classes. When I just can't face another day of cardio on my own, I take a spin class or circuit training class. Kick boxing doesn't work for me because I'm so uncoordinated that I have to do the moves really slow and it doesn't end being a good enough workout (plus I feel like a total loser doing it), but if you like it, then I definitely think it would help with the boredom factor.
My Before and After Pics
"Decide what you want; decide what you're willing to exchange for it; establish your priorities, and go to work." --H.L. Hunt
"Life has hills. Set the treadmill at an incline."