Well at a glance, shared vars for threads, need to be scalars.....I don't think it can be an object reference...... so maybe that would be a worthwhile feature of threads in Perl6?

I know now in Tk, I need to have a timer running to read shared vars in a thread. A thread dosn't affect main's globals automatically.. An interesting trick I didn't try yet was communicating back thru filneo's......the threads all share those fd numbers.