See:  http://clug.net.nz/index.php?Approx

Approx is set up on Tosh - See:  http://www.tcn.bowenvale.co.nz/content/view/51/42/#0001

The Sources file for a machine to access this is:

compaq-pro:~# cat /etc/apt/sources.list

deb http://tosh:9999/debian     sarge            main non-free
deb http://tosh:9999/security   sarge/updates    main non-free
deb http://tosh:9999/backports  sarge-backports  main non-free

# since this gave us access to 2.6.18 kernels, i guess etch has gone stable
# deb http://security.debian.org/ stable/updates main non-free
compaq-pro:~#

This assumes that 'tosh' is the machine with the approx cache and that the machine can resolve the cache.