Flowtime Time Management Software
Flowtime is a free and open source time management application for Linux. It is written in vala and released under GNU General Public License v3.0. It is based on flowtime working technique. Using this app you can take appropriate breaks without loosing you work flow. In this technique the work time is divided by 5 to get the break time. like if you worked for 100 minutes, then you will get 20 minute break. It comes with customizable alarm tones for break and notification break time.