General search engines
http://duckduckgo.com/ Also available: the DuckDuckGo browser.
http://www.yahoo.com
http://www.bing.com/
http://www.baidu.com/ (Chinese)
http://www.exalead.com/search/
http://www.gigablast.com/
http://www.volunia.com/
http://www.yandex.ru/ (Russian)
https://wbsrch.com
http://www.blekko.com is no longer online after being acquired by IBM Watson and shut down
Children’s Search Engines
www.8-12.info (Dutch)
http://www.fragfinn.de
http://www.blinde-kuh.de
http://www.helles-koepfchen.de
http://www.pklifescience.com (English)
Metasearch engines
http://www.dogpile.com – returns the most relevant search results from leading search engines
http://clusty.com – returns clustered search results, grouping them into categories
http://xoost.com – shut down – a social search engine which let you socialize with other people on the basis of common search queries
http://www.blingo.com/
http://deeperweb.com/
http://www.excite.com/
http://harvester.kit.edu/jss/special/harvester42
http://www.hotbot.com/
http://info.com/
http://startpage.com/
http://www.kayak.com/
http://www.mamma.com/
http://www.metacrawler.com/
http://www.mobissimo.com/search_airfare.php
http://www.otalo.com/
http://thiv.net/
http://www.webcrawler.com/
Real-time search engines
http://topsy.com – a social search engine that follows and tracks conversations on Twitter; also offers social analytics and trends
http://www.oneriot.com – shut down – was first launched in 2008 as a search engine and was acquired by Walmart in September 2011, when it shut down its search portal, focusing on ads network
http://www.scoopler.com – shut down – Scoopler is no longer running as the developers have been contracted to work on Google+ (source: Wikipedia)
http://www2.sandbox.google.com – shut down – an “under the hood” Google search engine for developers and programmers
http://www.scour.com/search/web/ – a multimedia search engine
http://collecta.com – shut down in 2011
Visual search engines
http://labs.systemone.at/retrievr – experimental search by uploading image or by sketch
http://tineye.com – reverse image search engine
http://www.yossarianlives.com – metaphorical search engine, returns results that are conceptually related to the search
Other search engines
http://onlinephdprogram.org/academic-research/– academic research engine
http://www.copyscape.com – duplicates search engine, detects plagiarism of web pages
http://www.artcyclopedia.com – art search engine
http://tools.seobook.com/authority-finder – shut down due to limited usage – allowed users to select which search engines to grab results from
http://www.kazzoom.com – shut down – extensive search engine which indexed more web pages than other search engines.
http://www.oamos.com – a meta search engine which queries for pictures, videos and even music related to the search terms
http://parkingspots.com – US & Canada parking spots location based search engine
Peer2Peer search engines
http://www.faroo.com/
http://www.seeks-project.info/site/
Mobile search engines
http://www.kooaba.com – image recognition search engine
http://www.acrossair.com – augmented reality type of search engine
http://www.taptu.com – social news reader for smartphones
http://vark.com – Aardvark is now shut down – it was based on questions and answers knowledge in an IM style interface
Vertical search engines (specialized on a topic)
http://furman.worldcat.org – search Furman University and beyond
http://portal.mace-project.eu/home – search for architectural content
http://www.liveplasma.com – visual music search engine
http://bing.com – web search engine by Microsoft (should be in a general section?)
Search engine with visual/logical navigation of results (other than plain list of results)
http://mrtaggy.com – social tagging search engine
http://www.viewzi.com – shut down – visual experience search engine
http://www.ujiko.com – shut down – a 3D search engine with a jukebox look
http://www.kartoo.com – a meta search engine with a visual interface
http://search-cube.com/ – a search engine that displays the results in the shape of a 3d cube
http://middlespot.com/search.php – shut down – an academic search engine with website preview
http://www.oskope.com/ – a visual search engine that queries Amazon, Ebay, Flickr, Fotolia and others in an interactive graphic interface
http://www.nexplore.com/ – website preview based search engine
www.eyeplorer.com – wikipedia visualization search engine – shut down
http://www.ziipa.com/ – shut down their search engine feature
http://trexy.com/ – metasearch engine which records users’ search history and allows deeper access to the web pages
Foreign search engines
http://www.baidu.com/
http://www.yandex.com/ – Russia, Turkey, Ukraine, Belarus, Kazakhstan
http://www.alleba.com/ – Philippines
http://www.ansearch.com.au/ – Australia
http://www.biglobe.ne.jp/ – Japan
http://www.ziplocal.com/ – United States and Canada
http://www.daum.net/ – Korea
http://www.yehey.com.ph/ – Philippines
http://www.walla.co.il/ – Israel
http://www.goo.ne.jp/ – Japan
http://leit.is/ – Iceland
http://www.miner.hu – Hungary
http://www.najdi.si/ – Slovenia
http://www.naver.com/ – Korea
http://www.rambler.ru/ – Russia
http://www.rediff.com/ – India
http://www.sapo.pt/ – Portugal, Angola, Cabo Verde, Mozambique
http://okidoki.ro/ – Romania
http://www.search.ch/ – Switzerland
http://sesat.no/ – Norway, Sweden
http://www.seznam.cz/ – Czech Republic
People search
http://www.mylife.com/
http://pipl.com/
http://www.ark.com
http://comfibook.com/
http://ex.plode.us/
http://www.peekyou.com/
http://backgroundchecks.org/
http://www.spokeo.com/
http://www.worldwidehelpers.org/
http://www.zabasearch.com/
Semantic search engines
http://www.hakia.com/ – business oriented semantic search engine
http://powerset.com/ – shut down – the domain redirects to Bing.com
http://www.spific.com – refined results search engine
Music
http://www.skreemr.com/ – became http://tunes.io/ – a daily playlist website
Research and experimental search engines
www.shmoogle.org – currently offline, search function does not work, but their Facebook page says they will release a new version soon
http://perspectoma.com/ – shut down – personalized search results on the basis of search and web history
http://blekko.com – curated, categorized results
Social search engines
http://www.mahalo.com – knowledge sharing service
http://thepiratebay.org/ – torrent files website and portal
http://porqpine.com/ – shut down
Natural language search engines
http://www.wolframalpha.com/
http://www.trueknowledge.com/- shut down
http://www.hunch.com/ – personalized recommendations
http://www.kngine.com
Document search engines
http://www.scribd.com/
http://issuu.com/
Privacy safe search engine
http://www.yauba.com/ – migrating, service coming back soon
Kids and religious search engines
http://quinturakids.com/ – content filter and safe search browsing
http://www.milkmoon.de/ – shut down
http://www.crossbot.de/
Art related
http://rhizome.org/art/exhibition/googleshow/
Keywords suggestion search engine
http://www.searchthetail.com/ – shut down
http://www.misspelling-generator.org/
Charity search engines
http://www.goodsearch.com/ – search engine which donates whenever it is used
Open source search engines
http://www.dataparksearch.org
http://www.gigablast.com
http://www.htdig.org/