Things could get really interesting if say the EU started incorporating a requirement for things that should essentially run fine on DC to compatible with DC. Universal power supplies (computers, phone chargers, etc) and brushless motors (washing machines) should really only require tweaks of their control circuits. AC motors (fridges/dryers/air conditioners) and microwaves wouldn't be an easy change. They'd either need a local converter or for demand to ramp up for explicit DC versions.
Standby power supplies (the thing that powers the IR receiver and power button while your TV is "off") wouldn't function as-is, since the common method is to use a capacitor+zener across the power line. But changing that to a rectifier + small switcher doesn't seem terribly onerous.