IBM and Yahoo! have teamed up to produce a new search engine dubbed IBM OmniFind Yahoo! Edition. This entry-level enterprise search engine is offered for free, with optional paid support delivered by IBM. The Flash demo looks promising, as is the "open source mash" done by the developers. I already knew Lucene, but this is the best looking package built around it I've ever seen so far.
I need to give it a try, it looks like a serious contender to the Google Mini (except that here you have to provide the server, which isn't downloadable for free from IBM.com ;-)).