A San Mateo, Calif. startup called Lucid Imagination is launching today with the goal of supporting (and making money from) Apache Lucene and Solr, open source search products that power high-profile websites like Netflix and Ticketmaster.

The “enterprise search” market, which covers both web site search software and tools for internal search within a business, has some big players — like Autonomy, Microsoft-owned Fast, and search’s 800-pound gorilla, Google. But Lucene (the search library) and Solr (the search platform built on top of that library) seem to be taking off. Lucid Imagination reports that more than 4,000 businesses have installed either Lucene or Solr, and that both are seeing around 6,000 downloads a day, which is between an eight- and 10-fold increase from three years ago. That’s pretty good for a business software, but it’s more impressive that major sites like Netflix are already using the product even though there hasn’t been a commercial entity offering support.

Chief technology officer Marc Krellenstein says Lucene and Solr stand out because they offer better relevancy and query performance, and they can scale into the billions of documents. The fact that they’re free and open source provides a nice incentive, too. On top of the free product, Lucid Imagination will charge for support; certified versions of Lucene and Solr; and additional software for system monitoring, improved search relevancy and more.

It’s easy to see why a powerful, free search product would be a hit, but with so many companies cutting back, I wonder if Lucid will still convince many customers to pay. Chief executive Eric Gries says that if Lucene or Solr is a key part of your business, it’s worth spending money to make sure it performs reliably.

The company has raised $6 million in a first round from Granite Ventures and Walden International. Solr creator Yonik Seeley is on the founding team, while Lucene creator Doug Cutting is one of Lucid’s advisors.