Timekeeping

Throughout history it's been necessary for time to be standardized into units and moments. As we continue developing approaches to personalized information presentation and representation-independent communication, we can start making up our own units. What habits of mind would change if one person worked on a 30 "hour" day, and another on a 10 "hour" day, corresponding to units that were intuitively meaningful to those individuals?

Would we be more effective at time management if we divided time into more meaningful units? Whoever decided that the optimal length for a lecture is quantized in units of hours?

Edit: As generally happens, I'm simultaneously out of my league and describing central questions to entire disciplines. See "The culture of time and space" by Stephen Kern for an introduction to the history of timekeeping.