Ancestry.com recently introduced a new genealogy-specific web search engine, called the Internet Biographical Collection. The service looks great but created a bit of controversy amongst web site owners whose sites were being indexed and cached. Today, Ancestry.com converted the new search engine to a free service, available to subscribers and non-subscribers alike. That conversion to a free service should eliminate most of the concerns.
Users must first register before using this free service, which seems like a trivial issue to me.
You can read Ancestry.com's announcement at http://blogs.ancestry.com/circle/?p=1785.
I have used the search engine and found it is rather good. Not perfect, but good. I was able to use the Internet Biographical Collection to find information on several web sites about a number of my ancestors quickly. So far, it hasn't uncovered any new ancestors but I plan to keep trying over the next few days. I suggest you try it at http://ancestry.com. A more direct route is to http://ancestry.com/search/db.aspx?dbid=1162.