www.fpctraffic.com is perfect for 404 traffic.
$3.00 PER 1000 RAW FIRST PAGE HITS
$3.00 CPM FOR POP-UNDERS
3 CENTS PER CLICK THROUGH
and you can also put on exit console on your pages so even when people close your 404 page you still make money! this way it pays for most of my hosting costs
and I like it because they can pay with epassporte.