I prefer the kind of trainer that can be folded up and put in a closet ............... and left there.

I truly hate my trainer. It compresses the worst of cycling into each event without any of the fun of going anywhere. That said, living in New England requires that I use it at least a little in the winter to stay in shape. To minimize the time spent on the evil machine I set the gearing to kill and ride hard till I can barely walk.