gRaphaël

Code

var chart = new Raphael("example"),
	lines = chart.linechart(0, 0, width, height, [[1, 2, 3, 4, 5, 6, 7],[3.5, 4.5, 5.5, 6.5, 7, 8]], [[12, 32, 23, 15, 17, 27, 22], [10, 20, 30, 25, 15, 28]], { nostroke: false, axis: "0 0 1 1", symbol: "circle", smooth: true }).hoverColumn(function () {
		this.tags = chart.set();

		for (var i = 0, ii = this.y.length; i < ii; i++) {
			this.tags.push(chart.tag(this.x, this.y[i], this.values[i], 160, 10).insertBefore(this).attr([{ fill: "#fff" }, { fill: this.symbols[i].attr("fill") }]));
		}
	}, function () {
		this.tags && this.tags.remove();
	});

	lines.symbols.attr({ r: 6 });