If you are mechanically inclined, your cherry on top could be metallic things or shapes having industrial design. When I was young at school, my favorite was sleek and streamline-shaped design like a product by Luigi Colani. His design gave me a somehow organic impression also.
Now I’m interested in classical shape rather than future one probably because, I suppose, there is beauty of sophisticated process and form in classical designs. For instance, A wheel cover of VW should be chromium plated, an airplane should have propellers and be painted with blue and white, a big ship should have huge funnel etc. Today we know hard chrome plating is not required anymore. Some thinner pipes are installed in the funnel. However, also we know, these designs are needed as a cherry on top.