Bubbles Screen Saver - description from Softdepia.com:
The Rising Bubbles Screen Saver places you underwater amidst a sea of bubbles.
Rising bubbles with realistic motion rise serenely on your screen, set over a backdrop of hundreds more bubbles comprising a blue-tinted bubble backdrop.
The Trial version will only play the screen saver for 2 minutes at a time just to give you a taster. The full version can be obtained from www.game-fun.net.
Bubbles Screen Saver is a "Free to try" program. You can download and try it for an evaluation period.