mongoclock

Description: Just a humongous clock for the terminal
Status: Feature complete
Source: https://git.maandree.se/mongoclock
Latest release: 3.1.5
License: ISC License (Internet Systems Consortium license)
Written in: C (ISO C99)

mongoclock is a simple, humongous, leap-second aware, digital, 24-hour clock for the terminal capable of display the POSIX time. It is customised by changing the font size and colour palette in the terminal. If the terminal is large enough, the second will be displayed.