Has anyone mentioned this tool recently for editing your small/kiosk/special use distro of choice? http://en.wikipedia.org/wiki/UNetbootin
Debian also has some tool for this, I forget the name. I tried it and I had to have a ton of crap installed to make it work. Didn't work for me. Permission issues out the rear and other problems.
Do a Google on remastering ubuntu (insert your own distro name here).