pomodoro.py

#!/usr/bin/env python
"""
Copyright (c) 2009 Blackgate Research.

This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license,
http://creativecommons.org/licenses/by-sa/3.0/."
"""
import time
import os
import sys

# Default values are 10 mins work, 2 mins play.
# Feel free to change to whatever works for you.
work = 600
play = 120

# Command to run each work/play play/work transition
notify_cmd = 'aplay /usr/share/sounds/speech-dispatcher/test.wav -q'

# Text to display
notify_text = (lambda: sys.argv[1] if len(sys.argv) > 1 else "WORK")()

# Main loop
while 1:
    os.system("clear")
    os.popen('notify-send "%s"' % notify_text)
    for i in range(0, work):
        print "%s" % notify_text
        print work - i
        time.sleep(1)
        os.system("clear")
    os.popen(notify_cmd)
    os.popen("notify-send PLAY")

    for i in range(0, play):
        print "PLAY"
        print play - i
        time.sleep(1)
        os.system("clear")
    os.popen(notify_cmd)

Originally found this method at http://www.43folders.com/2005/10/11/procrastination-hack-1025, it has become popularised as the "Pomodoro Technique".