Owen Williams explains in this article how he has improved its productivity with a setting on MacOS which allow a synthesized voice to announce the time each hour. It works as a reminder to focus on his work rather than procrastinate.

Here is how to implement the same functionnality on Debian/Ubuntu.

You need Espeak for speech synthesis and Mbrola to improve the result with a pleasant voice.

sudo apt-get install espeak mbrola mbrola-en1

You should now be able to make your computer speak with this command :

espeak -s 140 -v mb/mb-en1 "It's "`date +%R`

The option -v mb/mb-en1 tells mbrola to use the enhanced voice and -s 140 allows to slow down the diction. The date +%R command gives the current time.

The scheduler needs to know the XDG_RUNTIME_DIR environment variable to correctly manage sound. You can check it with the command env |grep XDG_RUNTIME_DIR, this should be something like /run/user/1000 in a typical debian/ubuntu setting.

With this information you can create a shell script /usr/local/bin/saytime.sh with this content :

#!/bin/sh

export XDG_RUNTIME_DIR=/run/user/1000
/usr/bin/espeak -s 140 -v mb/mb-en1 "it is "`date +%l` o'clock"

and add the line 0 * * * * sh /usr/local/bin/saytime.sh in cron with the command crontab -e in order to execute the script each hour.