How cool is this? It's a clock that counts from 00:00:00 (midnight) to 24:00:00 (midnight), but only increments when it reaches a prime number for its six digits. So, it goes 00:00:02, 00:00:03, 00:00:05,...,00:01:03, right through to 23:59:51 (since 235,951 is prime). Apparently, there are 7,661 time-primes between 0 and 240,000, so the clock increments on average around once every five seconds. Unfortunately, it's (a) not very accurate, (b) a bit pricey and (c) quite ugly. But a lovely idea nonetheless.
Thanks to Rob for pointing this out :)
