If you float two coffee beans in a cup of water that is being vibrated by your subwoofer (go to a sin wave generator online), the two beans will either be attracted to the sides of the cup or if positioned right will be attracted to each other in an accelerating manner. What phenomenon is this, and could it be related to gravity in space?
I think it has more to do with surface tension.
Added: When an object is floating on the surface of water, it bends the surface to support it. This bending extends outward from the object decreasing with distance (much like gravity). When 2 objects are near each other, they feel the bent surface and move down the slope (they attract each other).