No, I haven't tried that and haven't even heard of it. I have seen the usual gels, liquid products and one that was really cool. It would pull moisture out of the air to feed the lawn. If you poured it out onto a table top it would be granular and then start getting wetter and wetter. I saw that one ages ago and haven't seen it since so I have a feeling it worked better in the demo than in real life.
I will be out at the IECA convention (International Erosion Control Assn.) in San Diego in about 3 weeks. That is probably the biggest show for that kind of thing. I will look and see if Readyplay is there and check it out if it is. Ewing is mostly in the South and South west so we don't have Ewing stores here but they will have a booth at the show so if Readyplay isn't displaying I will try and check it out with Ewing.