Universal Laptop Power Supply?

Why don't we have a universal power supply for all laptop and notebook computers? Most of them are spec'd to the point where they are fairly similar, as evidenced by the iGo Power Supply that works with over 100 laptops. The only major difference between a Dell power supply and a Toshiba power supply is the connection in the back of the laptop. That's stupid. The power supply connector on a laptop is not a feature!

I don't pick my laptop based on which style of power supply I use. All I need to know is that my laptop power cord will connect to a standard grounded power outlet in the United States (and possibly work internationally as well). When I lose my power supply or the cord gets damaged, I should be able to walk into any electronics store and pickup a new one, or borrow one from some kind soul who has a fully charged battery. Instead I have to buy something like the iGo, which is universal, but also requires me to get a bunch of extra tips that don't connect with anything I own.

Jason Dunn takes power connector issues a step further, outlining his own power woes. Jason dreams of a world where add-on power solutions are more universally compatible, which would be easy if we could get everyone to agree on making power cords standardized on laptops across the board. Jason's right that getting individual brands to remain consistent throughout their product line is a good first step. But unifying the Dell, HP, Toshiba, or Lenovo product lines doesn't go far enough - the power cord should be universal on the laptop side, just like it is on the side that connects to the wall.