If you are someone who is goal oriented and who wants to keep an eye on their time, you will want to find a good online countdown timer. It helps with productivity and it helps you to keep on deadlines. We use a countdown timer ourselves, and our favorite free online countdown timer is at Online-Stopwatch.com.
When you get to the website, you are going stopwatches online to see a lot of stuff for sale - egg timers, gadgets, and other kinds of fun stuff. But the online countdown timer is free... a lot of the money that they make, we think, comes from Google AdSense.
If you go and click on the countdown timer, you'll find that it can be set to 50 minutes. Then reset it and it will start the countdown. What really works well when you're on the road is to make a smaller box within your browser and show the timer.