Any model you make which isn't 1:1 scale with a minifig is off-scale. There's micro-scale, mini-scale, macro-scale, and many others, I'm sure. I love the form of mini- and micro-scale building, since there's a creative and technical problem: how few pieces do you need to convery the essence of the object. It's elegant. And it's difficult. Here are some of the better attempts to come out of 'the toy room.'
I'm also using this page to present similarly small objects, like the double-decker sofa I built inside a deep-fill photo frame.