With this clocktower, you can keep time in your minecraft world. It resets itself every morning at the same time, even if you sleep in a bed. So it can always be counted on to be accurate. It plays the Westminster chime as it resets every morning. All this, wired to four faces, and small enough to fit in a tower that's only 11 x 11 x 36 blocks!
You could make the tower as tall as you want. This is about the minimum height. You could make it shorter with a different roof design.
Works best when built within the first spawn chunk.