My friend owns a very popular image host. Last time I checked (a few days ago), he was using 18 gigs of space and several hundred gigs of bandwidth. He just got nearly 800,000 unique visitors last month and has over 10,000 this month I beleive. He keeps all image on the site forever.
The site is
http://www.click2host.us however it is down due to a redesign by me and his host kicked him off their hosting for using too much of the server power. :P