I don’t use cardio machines a lot, but when I do, I prefer the StairMaster (stepper, stair climber, whatever you want to call it).  It’s different enough from running, which I can do outside, I tend to work harder on it, and I can read a few paragraphs from a fitness magazine (I can read- I just can’t talk!) while working out.  I cannot read on a treadmill or elliptical trainer.
Set your stair climber on manual for this simple and very effective workout.
Warm up:
5 minutes easy, building to moderate
Workout:
1 minute hard- RPE 6-7 (I went up to 135 steps/min)
1 minute moderate- RPE 5 (I recovered at 120 steps/min)
Repeat 10 x.
Warm down and stretch.
Make sure you read over my blog on what not to do before getting on the stepper!