waves.py

import time

numchars = 41
wait = 0.25
x = "."
o = " "

def wave(x, o):
    for num in xrange(1, numchars, 2):
        time.sleep(wait)
        print "{0:{1}^{2}}".format(x*num, o, numchars)
        
while True:
    wave(x, o)
    wave(o, x)