Apache Solr Instant
Updates search results as the user enters text. Something of a proof of concept. Does not update filter blocks, but we may be able to integrate with the Apache Solr Ajax module at some point.
Much thanks to the developers of the Apache Solr Autocomplete module, from which much code was borrowed.
Depends on the Apache Solr module.
Installation: Turn the module on and go to /search/apachesolr_search. Start typing and your search results should come up without submitting.