Well here is my first tips on where to place your ads on a forum. Its pretty obvious, but I still hope this can help those who dont know where to put the banners. I have been running a forum with 25,000 + members for a few years now. My niche is not the best for earning money on that particular forum, but I still get some dollars ;)

I will provide some screenshots to show you where on my forum I put the adsense banners, it works good with other ads as well, but adsense is what I mainly use at this forum..

First I put a banner after the first post for guests only like the one below

afterfirstpost.jpg

I also put one after the last post on each page in the topics. Visible for everyone, both members and guests.

afterlastposteachpage.jpg

and the last position is one at the top inside each forum category

forumindex.jpg

Im using vBulletin on this site, but it does not matter what forum software you use, just place the banners strategically correct and you will earn money. If you have a blog and a gallery for your users you should add some banners there as well. You can also add banners in their memberinfo page and your forum archive

You can also put one in the header that is visible on absolutely all pages. Hope this little forum monetization tips helps you to earn a few more dollars :)