On some Design News message boards, we've discussed how great it would be if consumer electronics like smartphones and tablets were rougher and tougher. What if you could actually drop one into the sink by accident, or into your plate of spaghetti sauce, and no harm would be done?A nanoscale coating that's now being applied to some smartphones will let you do that (though we don't recommend it). Aridion, developed by P2i, is used by Motorola on its RAZR and XOOM phones, and by Alcatel on its One Touch phones. About 30nm thick, or 1,000 times as thin as a human hair, the hydrophobic polymer coating is applied to completed products at the end of