So I insert the MacOS X 10.4 install disk, boot from it, select Disk Utility from the Start menu, and choose the volume of the new Mac. I use the Restore tab, drag and drop the old drive as the source, and the new one as the target, and press the button. Et voila! After copying, I can boot the new Mac with an exact clone of the old one. This seems obvious, but I haven't seen it mentioned here before.
[robg adds: This technique may result in some issues if the machines aren't nearly identical -- as a matter of practice, I never clone an old machine's startup drive to a new machine, given that I don't know exactly what changes have been made on the new machine. But if you're setting up a number of identical machines, this could be one way of speeding the process.]

