My PowerBook's original power brick died. Well, actually, the bit where the cable met the laptop-end power plug fell apart. I got a replacement, and that one did, too.
Now I have a MacAlly replacement. It's less pretty, but it seems more durable. Sometimes the cable that runs from the brick to my laptop comes out of the brick, but only when I'm moving around.
The brick has a bright blue LED to tell you when it has power. The LED is very near where the cable connects, and when I pick it up to plug it in, I can see blue light coming out through the cable's socket. It always makes me feel like the laptop is powered by blue light.