install or clone windows over network unattended?

I need to install windows Xp Pro on 24 computers, but would like to either clone them from a preset computer, provided the hardware matches on all machines. Or I would like to install it on all machines. I would like to install them over the network fully unattended, and without my presence being there after install is underway. I would prefer for the install to take place around 7:00pm-12:00am after school is out, so as to not interfere with student's work. could someone shed some light on a fast inexpensive approach?

 

Like this? http://unattended.sourceforge.net/
A power point someone has posted about the program:
http://legacyweb.triumf.ca/hepix2003/pres/21-12/resposito/unattended-eng.ppt.

Another write up:
http://www.itpro.co.uk/88300/setting-up-an-unattended-network-windows-xp-install

 

Also there is a project called FOG -
http://www.fogproject.org - it is called a 'free ghost' solution.