I wish we could get rid of them all. I hate the stupid huge banner when I'm reading. I hate the stupid posts and stupid threads written just to get sig views. I hate having to scroll down past them. I hate having them on the screen, blasts of useless eyecatching colors in between the posts I want to read. I hate having to try and decide if the poster is stupid, ignorant, in need of help, or just trying to earn a few satoshis.
I hate hate HATE them.
Ban them all.
Forever.
You do not want advertisements on this forum. May be you are not aware about how websites or forum operates. There are huge costs like hosting fess (which must be huge for a large forum like this). How do you plan to cover those expenses if all those advertisements are removed. Regarding rewarding users with bitcoins in forma of signature campaigns, I think it is one of the reasons behind the huge success of this forum. Suggestions like limiting the number of posts required do appear somewhat practical.