Thanks to tipster Otis Gospodnetić, we find a library for running Lucene.NET on Windows Azure. The library uses a local cache on the file system where Lucene is running that is also backed up by Azure Blob Storage. This technique allows many index "workers" to update and read from the same index without having to hit cloud storage for every operation.

The creatively titled Azure Library for Lucene.NET was uploaded to the Microsoft Code Gallery by a Microsoft Engineer.

Lucene is a very high performance indexing and search engine that can be used to search a catalog of free text documents. There are some big names that use Lucene including the Stack Exchange Q&A network, the "noSQL" Raven DB, Autodesk, and many others. This library provides one more option for creating a quick search engine in the cloud.