Make wget download page resources on a different domain
wget --recursive --level=inf --page-requisites --convert-links --html-extension \
--span-hosts=domainA,domainB url-on-domainA
UPDATE: I remember the command above worked for me in the past (that was 2010 and I was using GNU Tools for Windows back then); however I had to change it to the following when I wanted to use it today:
wget --recursive --level=inf --page-requisites --convert-links \
--adjust-extension --span-hosts --domains=domainA,domainB domainA
The shorthand for that would be: wget -rEDpkH -l inf domainA,domainB domainA
-r
=--recursive
-l <depth>
=--level=<depth>
-E
=--adjust-extension
-p
=--page-requisites
-K
=--backup-converted
-k
=--convert-links
-D <domain-list>
=--domains=<domain-list>
-H
=--span-hosts
-np
=--no-parent
-U <agent-string>
=--user-agent=<agent-string>
GNU Wget Manual: https://gnu.org/software/wget/manual/wget.html