https://httpheader.net/
http://httpheader.net/
http://azenv.net/
http://ip.spys.ru/
http://proxyjudge.us/azenv.php
http://www.proxyfire.net/fastenv
http://www.ingosander.net/azenv.php
http://www.proxy-listen.de/azenv.php
http://rosinstrument.com/cgi-bin/isanon.pl
# http://www.anonymousproxylist.net/azenv2.php
# https://www.anonymousproxylist.net/azenv2.php
# http://ip.cc/anonymity-test.php
# http://www.all-nettools.com/toolbox/environmental-variables-test.php
