This is what I use 95% of the time:

– Kettlebells 12kg, 16kg, 20kg, 24kg
– 1.5 x 1.5 meters of space in my home office

This is what I use about 5% of the time:
– Dumbbells 3kg and 7kg (bought them both to rehab my golfer’s elbow)
– Gym mat
– Olympic rings
– Floor slides

I’d use the rings and TRX more if I’d set them up somewhere other than the backyard.

As for the gym mats, I just can’t be bothered to set them up before each workout. I mean, it takes at least 18 seconds to piece them together.

It just goes to show that to make a habit sticky, convenience is the way to go.