Just as an aside, it's high time there was a serious effort at producing a decent open source search. Personally, I think a distributed network with anonymizing services makes the most sense. I know there are projects in existence already, but more people will have to become aware of them. Some Open Source search projects are:

http://www.majestic12.co.uk/projects/dsearch//

http://www.aspseek.org/about.html//

http://sourceforge.net/projects/ebiness//

http://www.grub.org/html/documents.php//

http://lucene.apache.org/nutch/bot.html//

I really want to see one of these projects take off, I'd tap a vein at the local plasma center to donate funds :>