Cited as a reference
Water Cooled Raspberry Pi 3
Why people recommend it
Linked several times with little comment, apparently as an existing example of an unusual Raspberry Pi project, and once as a more elaborate way of cooling the board.
Watch for: Community gives little detail on its contents
In their words
But if you need any other more cool option, you should check out this one:
Anshul Bansal on raspberrypi.stackexchange.com, Apr 2017. CC BY-SA.