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More information about the errors in the (fixed point) math on the patriot: http://www.ima.umn.edu/~arnold/disasters/patriot.html

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That's interesting.

Given that it was an issue with a non-terminating binary representation, what would be the way to handle this, without somehow resetting the clock (restart or otherwise)?

Obviously, you could, in a modern system, have more memory and be able to store more bits of the number, but there would still be a limit that you would run into after some amount of time that would cause similar problems.

I'm just thinking about this. I think I would try to split the clock into a precise part, which (for example) tracks how many milliseconds we are into an hour and a precise part which stores the hours, or the date up to the hours or whatever. Given this, I can reset the part with the degrading accuracy in a duration which maintains enough accuracy in order to maintain enough accuracy overall.

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