Jason made a DIY space invaders clock using propeller-generated video on a vintage Sony tv, he writes-

I started out today with the goal of just displaying the time digitally, but I got sidetracked with the idea of representing the time with icons instead. I ended up going with this spacer invaders concept, using the number of aliens to represent minutes (0-59) and the extra lives represent hours. The last 4 digits of the high score also read out the time.

This is double-buffered, flicker-free video being generated by a propeller chip. Unfortunately the double-buffering uses up a ton of chip ram and I may have to scrap it to add more features eventually.

space invaders clock – pr0jects! – Link.