Classic Nordic Track ski machine plus Powerblock dumbbells?[2]

That's what I have.

My main aerobic exercise is walking outdoors, but for high-intensity aerobics I've used a classic Nordic Track ski machine since the late 1990s. I don't fold mine up, but it is made to do so to slide under a bed, and I'm told it can be stored vertically folded up with some modification[1]

I like the ski machine because it is low impact, I get some arm exercise, and I can read on my iPhone while I exercise. It takes a little getting used to - I first tried it out in a gym where they had a trainer until I got the hang of it, then purchased one.

I pace indoors, too - we have a long enough straight space to make that practical while I read.

I bought the Powerblock dumbbells to have a lot of flexibility with a compact set, though since I bought the vertical stand, I don't know that I'm saving that much space.

[1] http://www.instructables.com/id/Closet-Storage-for-a-Ski-Machine-and-Other-Modific/

[2] http://www.powerblock.com/Classic%2050%20Set.php