I have been kicking myself for 3 years since installing our pool that I didn't put lighted bubblers on our tanning ledge. I even looked in to getting them replaced but with the concrete work, etc. it just didn't make any sense.
Enter the product I found yesterday. These screw into the returns and have a little impeller that powers a generator that powers 8 LEDs. No wiring, no trouble and only $30.00 each. I figured they were worth a try.
For my application on bubblers, they work awesomely! They don't throw a ton of light so I think in a pool lighting scenario they wouldn't do that well but when uplighting a stream of water from bubblers they are perfect.
I have no affiliation with these at all other than they solved a problem for me I thought was unsolvable. Time will tell how long they last but for now they are perfect.