If you're looking for a clock with that little something extra, then take a look at the rather original PolarClock Widget.
PolarClock widget displays months, days, hours and minutes in colored circles which swirl around until at the end of the month, when they presumably make a complete circle. At first, it looks very confusing but you'll soon work out that the seconds are the outer band, minutes the next inner band, hours the next and so on until you reach the month in the middle. The colors are a pretty psychedelic and it can be a little mesmerizing but nevertheless it's an original widget that's also available as a screensaver on the developer's site.
PolarClock isn't exactly an essential widget but it's something a little out of the ordinary as far as timers go on Macs.