Revenue from Torrent Trackers?

I run a torrent tracker with a large permanent membership base and a fair bit of traffic on popular seo'd torrents.

Whats the best way to get revenue out of this traffic ?

I have tried various PPC type advertising with little success. I am considering CS and Adult aff's/banners and wotnot.

nb. this post is to get the ball rolling and i will add more as we go.
unfortunatly i cant mention the sites url in the open as they are whitehat atm (well as white hat as you can be with a tracker )