My original justification/inspiration for spending money on another pi plus pretty lights was this tweet - a word clock. Very cool!
However instead of doing that, I started thinking of other (easier?) ways of displaying the time, and this is what I came up with:
Obviously a normal (cubic) die only goes up to 6, but with 9 available dots it doesn't take too much effort to add in a few more numbers. Zero shows no lights, so midnight looks a bit boring...
The unicorn hat python library meant this was minimal effort, once I'd written out many lists of pixel co-ordinates - followed by several weeks of laziness before I tidied and commented the code and stuck it on github.
The LEDs on their own are a bit harsh, so my current temporary solution is to use a bit of paper to diffuse it. This does not photograph particularly well, so you'll have to use your imagination