This is very useful for anyone who prepares used macs for sale.
Many times a mac of a year or more older would install to an OS version that isn't the latest, and isn't the best user experience to get a "new" mac, then have to spend a couple of hours downloading updates.
With this method you can setup a generic user after the fresh install, do all of the updates, and any freeware/shareware programs that people may find useful, then do the prep steps in this hint.

There will likely still be a handful of updates depending on how long between prep & purchase, but especially with some of the iLife updates being over 1 GB and the Combo updates being close, it really is better customer service.

If you're doing this often, it's better to make a generic clone or netrestore-type of image and install that after erasing and zeroing out the data on the HD. No commands and reusable. Just ensure you provide the discs for all those 3rd-party apps you put on the machine that aren't freeware.