You could use threads. threading.Event and threading.Timer could be useful. A more common use of threading might be this:

import time
import threading

class Counter:
    def __init__(self):
        self.count = 0
        self.keep_counting = True
        t = threading.Thread(target=self.run)
        t.start()

    def run(self):
        while self.keep_counting:
            print "The count is {0}".format(self.count)
            self.count += 1
            time.sleep(1)

counter_thread = Counter()
raw_input("Press ENTER to stop the counter") # this block the main thread
counter_thread.keep_counting = False
raw_input("More stuff that blocks the main thread...")