Spiderzilla is an easy-to-use website mirror utility, based on Httrack from www.httrack.com.
More infos on http://spiderzilla.mozdev.org/ .
Do you want to translate it into your own language or suggest corrections??? See the babelzilla.org project for easy translation! (inscription needed).
Actually i don't have time to continue to develop this extension... if anyone wants to participate, it would be very interesting for everyone that wants to see this project improved