LlSetBuoyancy

Caveats

Wind can cause the prim to drift. (server 1.38.4 this appears not to be true)
Unlike some other characteristics, this is cancelled if the script that set buoyancy is removed from the prim.
This function cannot be used to set relative levels of buoyancy in parts of a linked object e.g. to simulate a helium balloon weighted by its string. The most recent call of llSetBuoyancy in any child prim appears to set the global buoyancy level for the object.
This function eats energy to keep the object floating. Large objects may not be able to supply enough energy to keep the object floating.

Makes an object float up slowly (e.g. a red balloon)

default
{
    state_entry()
    {
        llSetStatus(STATUS_PHYSICS, TRUE);
        llSetBuoyancy(1.05);
    }
}

Often used to make an object look like gravity does not affect it.

Signature
function void llSetBuoyancy( float buoyancy );

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