Lightning Component for Wikipedia Search , Blog post - http://www.jitendrazaa.com/blog/salesforce/lightning-component-for-wikipedia-search/

WikiSearch.cmp.html

<aura:component controller="WikiHttpRequest" 
                implements="force:appHostable,flexipage:availableForAllPageTypes">
	<ltng:require styles="/resource/SLDS090/assets/styles/salesforce-lightning-design-system.css"/>
    <aura:attribute name="txtWikiText" type="String"/>
    <aura:attribute name="resultLimit" type="Integer" default="4"/>
 
  <div class="slds-card">
  <div class="slds-card__header slds-grid">
    <div class="slds-media slds-media--center slds-has-flexi-truncate">
      <div class="slds-media__figure">
          <c:svg class="slds-icon  slds-icon--small slds-icon-standard-account" 
                 xlinkHref="/resource/SLDS090/assets/icons/custom-sprite/svg/symbols.svg#custom68" />
           
      </div>
      <div class="slds-media__body">
        <h2 class="slds-text-heading--small slds-truncate">Wikipedia Search</h2>
      </div>
    </div>
  
  </div>
  <div class="slds-card__body slds-box slds-theme--default">
      <div class="slds-grid slds-wrap">
          <div class="slds-col slds-size--10-of-12">
          	<ui:inputText value="{!v.txtWikiText}" placeholder="Search Text" class="slds-input" 
                          keyup="{!c.searchWiki}"/>    
          </div>
          <div class="slds-col slds-size--2-of-12">
          	<button class="slds-m-left--small slds-button slds-button--icon-border-filled slds-button--icon-small" onclick="{!c.searchWikiOnButton}">
                <c:svg class="slds-button__icon" 
                                 xlinkHref="/resource/SLDS090/assets/icons/utility-sprite/svg/symbols.svg#search" />
              <span class="slds-assistive-text">Settings</span>
            </button>
          </div>
          
          <div class="slds-col slds-size--10-of-12 slds-p-top--large"> 
              <ul id="resultPlaceHolder" class="slds-list--vertical slds-has-cards slds-has-inline-block-links--space">
                  <!-- This is placeholder to render Wiki Search results -->
              </ul>
          </div>
          
          <div class="slds-col slds-size--2-of-12"></div>
        </div>  
      </div> 
    </div>
    
</aura:component>