a concurrent programming abstraction

Hi,
This may not be the best place to post this question, but I didn't
know who to ask, so sorry if this is a bit off topic.

I have the following algorithm, that I want to execute in a separate
thread, so that I do not block the main one:

void findBest()
{
    for ( Element elem : collection )  // foreach
    {
        Score score = ComputeScoreIn25minutes( elem );
        if ( score > bestScore )
        {
            bestScore = score;
            bestElem = elem;
            // iterruption point here
        }
    }
}

I could use a future<> abstraction as described in N2094, N2185,
N2276, but I do not really have to run my algorithm to an end. I would
like to be able to obtain the best element found so far rather than
wait till the algorithm computes score for the last element in the
collection.
Thus, I would imagine starting my algorithm similarly to how a future
is created:

QFuture<elem> qfuture = run( ... );

Now, calling qfuture's default operation would interrupt the thread
rather than wait until the thread finishes.
I wonder if anyone here have ever thought of something similar. If it
is already implemented. If it has a name. Or if it is possible to
implement such an abstraction, that would not be too intrusive to
function 'findBest' from my example.

I would appreciate any help,
&rzej

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