Why do you put every filter on a different domain instead of one domain - say filtercyborg.com - where you can use all the filters?
From past experience we know that our user will use only one filter and forget about all the other. Having 10 and plus filter tend to overwhelmed most user. We believe in the DOTADIW concept : "Do One Thing and Do It Well."
Got it. Have you had success with that? Is one of your sites used heavily now?