Even though I was moderately pleased with my simple coasters last week, I knew I could do something better to go with our new coffee table. Taking a design hint from the table itself, I replicated the river style in a much smaller format. I've used blue flourescent perspex several times before to give the same water effect.
I took a second cue from my Carcasonne River Expansion, each tile aligns with all the other tiles in any combination. the river edges all meet at the same point and the same direction so which ever order they go in they'll form a nice looking river.
The bottom layer still had to be full size and I had to include some material between the two banks to keep the halves separated. The effect works but I keep thinking about how to do that better.