var chartsize = 54;
    var features = [];
    for(var i=0;i<4;i++){
        features.push(
            new OpenLayers.Feature.Vector(
                    new OpenLayers.Geometry.Point( -13630365 + 10000 * Math.random(), 4543034 + 10000 * Math.random())
                    , { img: "http://chart.apis.google.com/chart?chs=" + chartsize + "x" + (chartsize / 2 + 4) + "&cht=gom&chl=" + i * 25 + "&chco=00f
f00,ffff00,ff0000&chd=t:" + i * 25 }
                ))
    }
    var style = new OpenLayers.StyleMap({
                               pointRadius: chartsize/2
                             , externalGraphic: "${img}"
                        })

    var vectors = new OpenLayers.Layer.Vector("graphs"
                    , { isBaseLayer: false
                    //, displayInLayerSwitcher: false
                    , projection: new OpenLayers.Projection("EPSG:4326")
                    , styleMap:  style });

    vectors.addFeatures(features);