Search engine Microformats Implementations that index microformats across the web (i.e. not just on their own site).
General web search. Search engines that index websites in general using microformats.
Google.com supports rel="nofollow", hCard 1.0, hReview 0.4 (in progress), hReview aggregate, hProduct (since 2009-05-12 for rich snippets), hCalendar 1.0 (since 2010-01-22), hRecipe 0.22 (since 2010-04-13) - in main search. See also related blog post on hCalendar hRecipe support and hMedia (since end of 2012).
previous search engines
Some search engines (or search engine backends) are no longer up and running, but when they were, they supported microformats:
Yahoo search supports rel="nofollow". Through additional interfaces, Yahoo supports rel="license" (Yahoo Creative Commons search) and hCard, hCalendar, hReview, XFN, geo, rel-tag, adr through Yahoo Search BOSS and Yahoo Search Monkey. See Yahoo Search for more details.
- VIREL (~2008-2010? http://virel.de/, site no longer does search as of 2011-222) indexes both hCard 1.0 and hCalendar 1.0 and provides a user interface (pop-up menu) to choose between searching contacts or events.
- 2008-09-09 Tag Edge: http://tagedge.com/2008/09/09/virel-microformats-search-engine/ (post permalink broken) Virel: Microformats Search Engine
- singpolyma social web search (XFN - The XHTML Friends Network, hCard 1.0) part of the diso project.
previous blog search
Search blog posts and blogs in general. Search engines that specifically index blogs, blog posts, and other realtime sources on the web using microformats.
- Technorati (rel="nofollow")
- Technorati Kitchen (~2006-2010? http://kitchen.technorati.com unavailable as of 2011-222)
- IceRocket through additional interfaces
previous search results in microformats
Search engines that publish microformats in their results (but may not necessarily be indexing microformats).
- Karniyarik Vertical Search Engine for Online Products (Stealth Beta was at http://www.karniyarik.com/karniyarik-web). Karniyarik's search results lists products and their vendors, which are marked up with hCard 1.0 (e.g. search results for bebek bezi - diapers). In addition, Karniyarik's about page is marked up with hCard.