Totally agree about “wall warts”, they are a nuisance for all of us. Surely consumer electronics companies could set a simple standard for DC power supplies, most things run on 5V or 12V and if there was a standard input plug for these two voltages we could do sensible things like have one power supply to power multiple devices.

The best power supplies are those that can either plug directly in to a wall socket (via a suitable local mains pin assembly) or accept a mains cord.

I think Apple’s DC power supplies are pretty much ideal. They’re small, light, and thin. They are also modular, meaning that you can easily swap out one country’s plug configuration for another. If all else fails you can fall back to a “figure-8″ power cord, which is reasonably standard. Not to forget details like the fold-out hooks for winding, and the mag-safe connector.

Apple have done a good job on their recent supplies but I did have the magnetic socket in the laptop pick up some little pieces of wire that were difficult to remove and risked shorting the supply. I wish a dc connector was a world standard.

Power supply plugs change frequently to stop us plugging the wrong one in, surely there is a better way to achieve that – perhaps by having a circuit to measure the incoming voltage and somehow complain if what ever is connected is outside the specified range.