This turned out better than I was expecting.
With a sloping up beach to get some back swash instead of the particles falling over the edge, I think this could work quite well.
One nice thing is that this will run on and on continuously, constantly changing, even though the actual waves aren't simulated. Actually its still just the one (slightly shoddily made) wave repeated numerous times in different areas. I think it would look better with less waves to be honest, but it was just a test.