I think my thoughts strayed this way because of the movie I'm watching right now at work.
Legally downloaded... Movielink is kind of cool.
Anyway... theoretical physics musing ahead.
I've heard it is debated if there is a smallest unit of time, just as there is a smallest unit of distance, or length.
Given that the smallest unit of distance is Planck's length;
Given that NOTHING travels faster than light in the material universe;
Then wouldn't the smallest unit of time be the time taken for light to travel Planck's length?
Just my 1/50th of a US dollar.
[Edit 11/03/05 12:28pm]
I guess I was right. I was bored, did a Google search for "Planck's length" and this was actually one of the first articles listed. Weird.
The smallest unit of time (time quanta) is the time it takes for light to travel Planck's length. (Planck's time.)
Since distance/relativity stop and quantum mechanics take over at Planck's length, actions across lengths less than this boundary are meaningless.
The fastest speed attainable is the speed of light (apparently).
So, if we take the smallest length and divide it by the fastest speed, we get the time it takes for the fastest thing to travel the shortest distance. Times shorter than this amount simply do not make sense.
SO:
Planck's length is about 1 x 10-34 m
Speed of light is about 3 x 108 m/sec
Planck's time is about 3.3 x 10-44 sec
And if you're particular about sources:
Physlink.com