Hook to leaflet to add ID to icon markers

gistfile1.js

(function () {
  var original_initIcon = L.Marker.prototype._initIcon,
      originalsetIcon = L.Marker.prototype.setIcon;

  L.Marker.include({
    setIcon: function (icon, id) {
      this.options.id = id;
      originalsetIcon.call(this, icon);
    },
    _initIcon: function () {
      original_initIcon.call(this);
      this._icon.id = "marker-" + this.options.id;
    }
  });
})();