If you haven't tried it yet, run to http://add-art.org/ and follow the install instructions.
It's even better than no advertisements.
It's also possible to propose some images there, and I think the stuff in the header of casarobino.org is very much in the right direction (well, actually not, since they also want vertical stuff). Whoever has been doing this great job of coming up with the pictures (who?) should really do it some time for add-art as well some time!
