I've been messing around with the Python library for BlinkyTape, modified it a bit and came out with a binary clock as another example.
It displays UNIX epoch time, and local time hours, minutes and seconds, updating every second.
There's still 10 (well, at most 12) LEDs left to tinker with.
You can grab it from my fork of the official repository (warning, the library is somewhat modified):https://github.com/kav2k/BlinkyTape_Python
To run: `python binary_clock.py -p <port name>`
Maybe I should pull request this?..
Here's a fun challenge, though it's not very hard: make an autonomous firmware that will make a binary clock (minus the epoch time), with time changeable via the button. I'll probably tinker with it myself.