Use jQuery to get a Pinboard tag for a given user.Pinboard uses the 'cb' callback method name in it's JSON.

gistfile1.js

function GetPinboardTag(user, tag, count, handler) {
  $.ajax({
    url:'http://feeds.pinboard.in/json/v1/u:'+user+'/t:'+tag+'?count='+count,
    jsonp:"cb",
    dataType:'jsonp',
    success: handler
  });
}