Finding a Travelling Companion

I have had an email from someone looking to share a cabin:

with a likeminded woman on a cruise going from Southampton to Auckland in 2011. It is expensive and as you know, singles are penalised by tour companies, particularly on cruises, where we have to pay excessive supplements. Do you have any idea where I can meet a woman who would like to join me. Perhaps a website, or an organisation I can join?

I found this site had some good ideas of links and advice http://www.women-on-the-road.com/female-travel-companions.html

Does anyone else have suggestions?