I need a new search mechanism for my site

Atomz.com recently announced that:

“To help offset the cost to continue to provide this service, we will be adding contextual advertising before and after the search results. This advertising will be delivered by Google, our advertising partner. The ‘sponsored links’ will be purely text-based and will be driven off the search keywords entered. They will be visually distinct from your search results, so your visitors know what results are for your site, separate from the advertising.”

I will not allow advertising on my site, and I know of a peer of mine who’s company is having similiar problems with this recent news. I’m sure I could probably use the default MoveableType search engine for my site, but that wouldn’t work for my friend.

Anyone know of a free search engine I can use for my site and/or others? It will replace the current search functionality I have now.