I have a thread created with Thread.new that does some polling.  I don't 
want it to busy wait so I call the sleep method like so:

sleep(60)

    ...this should allow me to poll every minute which is good enough for my 
application.  However, I'm finding that calling sleep from a thread in this 
manner often sleeps for a good deal longer than a minute.  So far, I find it 
sleeping for about 8 or so minutes.  The main thread is blocked in a gets 
call.
    What I'm actually trying to do is implement a simple timer.  I'm trying 
to do something at a certain point in time, like a cron job, without busy 
waiting.
    Why is sleep behaving so strangely?  Is there a simple way of doing what 
I'm trying to do?
    Thank you...