Not an easy solution
This is not going to be easy. The main reason for all the different power cords and adapters is because most electronics do not run or charge on the same voltage. The whole point of having a unique adapter is to make sure that someone doesn't accidentally plug a 3.3V charger into an electronic system designed for 1.5V, frying the delicate electronics. It's not reasonable for small handheld electronics to have a transformer built in, since this would increase the size of the system significantly. It is equally unreasonable to have a standard charging voltage, since this is determined by the thermal dissipation capability of the system (obviously the higher the voltage, the faster the charging, which means the higher the thermal "heat" generation).
The only way of getting around this is having variable transformers that receive charging information from the product they are charging so that they increase/decrease the voltage they are providing to the product in question. The problems with this is that the charger would be pretty large, fairly inefficient, and would only be able to work with the components it's programed to recognize. Still, it's a workable solution.
P.S. What is not standard about USB cables? Male/Female, Type A, Mini B. What more do you want?!!?