Some ideas, as a base for discussion:
Split the forum load, all pics etc from a cheap non off shore server (Host in the Netherlands, cheap and secure), only the sensitive data (site access etc on a secure off shore) Block all irrelevant traffic, avatars, signatures etc.. Automatically delete / block all quoted pictures Restrict image size Charge the collectors traffic fees on their posts Close all discussions after page one for non paying members block all pictures for non paying members
hope this helps