Project Ocean is designed to provide realtime search capabilities. It is pre-alpha with an Apache license. Developers and corporate sponsors welcome.
The genesis of the idea was at a social networking company using Solr who wanted realtime instead of batch updates. At first I tried making Solr do this. Then decided to build a core and a server around it figuring the core could be later integrated into other projects. It has been a part time project that needs resources to deliver a version 1.0. http://code.google.com/p/oceansearch/