static void Main()
{
Queue queue1 = new Queue();
Queue queue2 = new Queue();
// ... operations to fill the queues with data.
// Process each queue in a separate threda.
QueueProcessor proc1 = new QueueProcessor(queue1);
proc1.BeginProcessData();
QueueProcessor proc2 = new QueueProcessor(queue2);
proc2.BeginProcessData();
// ... do some other work in the meantime.
// Wait for the work to finish.
proc1.EndProcessData();
proc2.EndProcessData();
}