>disposable hot towels / icy cold napkins

Why don't we see this at every restaurant?

The server brings out a teapot and a little nubbin on a plate. What sits on this small plate is a white cylinder stub resembling a marshmallow, the size of five stacked nickels.

She pours steaming hot water onto this paper nubbin lying on its side, and voila, it expands tenfold lengthwise, the incredible Hulk-like, ready for you to unfold it.

Ooh, a hot napkin... and icy cold versions in summer.