I'd like some way to make the labels always visible in my chart. I currently have a legend but I would ideally like to be able to get rid of it and have something more like:

Only thing is I can't really work out if this is possible with the visualization API. I can set the pieSliceText option to 'label' but that will only show if there is considered to be sufficient space inside the slice (which seems to be pretty rare). The information I get for the tooltips would do but it doesn't appear to be possible to make them always on.
Any suggestions?
Thanks,
-- S