A set of brass knuckles with a cellphone integrated into the palm.
Don't leave home without it!-- 8th of 7, Jun 21 2011 You forgot the "the" between "leave" and "home".-- MaxwellBuchanan, Jun 21 2011 'Home' can be adverbial, and therefore doesn't need a 'the.'-- RayfordSteele, Jun 21 2011 It does when it's a special care facility for the mentally deranged.-- rcarty, Jun 22 2011 Wouldn't the screen be rather small?
Also, I'm thinking about the need for the knuckle linkage to work both in open- hand and in clenched fist cases. If the phone were snug against the palm when the fist was clenched, then a rigid linkage would cause the phone to flap loose when the fingers were opened. And the fingers would have to be opened to allow the fingers of the other hand access to the phone, so as to operate it.
If you attached the phone to the palm with a strap that passed over the back of the hand, that would work, but there would not be any significant connection with the brass knuckles.
Given that the phone/ knuckles integration is required here, some sort of hinge-and-spring arrangement would seem to be indicated.-- pertinax, Mar 16 2021 random, halfbakery