Free search service. Crawls your documentation every 24 hours

Hosted Search API that delivers instant and relevant results from the first keystroke.

This is a collection of classes that can be used for Approximate matching, searching, and comparing of Strings. They implement algorithms that compute the Levenshtein edit distance, Sellers edit distance, the Hamming distance, the longest common subsequence length, the longest common substring length, the pair distance metric, the Jaro-Winkler metric.

Get the Chrome/Firefox all-in-one search and address bar in Safari. Requires SIMBL.

Reverse image search - useful for spotting scammers or copyrighted image library photos. Free for personal use (Firefox plugin) or commercial pricing for the API

An interesting-looking schemaless, distributed, RESTful search engine, built on top of Lucene, with built-in support for multi-tenancy, data sharding, failover and automatic state restoration /via @timblair

Ruby gem to connect ActiveRecord to Sphinx

Embed Google things (maps, calendars, searches, comments, etc.) on your site

Awesome UK property search engine with a lovely endless-scrolling dynamic interface

It now pretends to be a MySQL database so you can write SELECT queries

“Unstructured Information Management applications are software systems that analyze large volumes of unstructured information in order to discover knowledge that is relevant to an end user.”

Instant domain searching via Ajax

Using Solr with Ruby

Ajax, GMap, search text

Fast results on a Google map

Ruby text search engine based on Apache Lucene

Safari Livesearch/Spotlight add-on